Animals That Start with M: Ultimate Guide to Stunning Creatures

The animal kingdom is a never-ending adventure, with new discoveries around every corner! Today, we’re setting our sights on animals that start with M. From the majestic Moose to the mischievous Monkey, the M animals list is a diverse bunch. We’ll delve into the world of both cuddly and creepy M creatures, from the playful Meerkat to the mysterious Manta Ray. So, grab your magnifying glass and get ready to be amazed by the fascinating M animal family!

Macaque

Macaques, classified under the genus Macaca, are sociable Old World monkeys belonging to the subfamily Cercopithecinae. Spanning 23 species, these monkeys are found across diverse regions including Asia, North Africa and Europe (specifically Gibraltar). While macaques primarily favor a diet rich in fruits, they also consume seeds, leaves, flowers and tree bark.

Certain species, such as the long-tailed macaque, occasionally add small quantities of meat to their diet, derived from shellfish, insects and small mammals. The size of macaques varies significantly based on their sex and species. Male macaques exhibit a head and body length ranging from 41 to 70 cm (16 to 28 inches) and weigh between 5.5 to 18 kg (12.13 to 39.7 lb). Female macaques typically weigh between 2.4 to 13 kg (5.3 to 28.7 lb).

Macaroni Penguin

The macaroni penguin (Eudyptes chrysolophus) inhabits regions from the Subantarctic to the Antarctic Peninsula. Recognizable by its distinctive yellow crest, which resembles macaroni, this feature gives the species its name. The penguin’s face and upper body are black, creating a stark contrast with its white underbody. On average, adult macaroni penguins weigh about 5.5 kg (12 lb) and measure 70 cm (28 in) in length.

Both males and females look similar, though males tend to be slightly larger and more robust, with comparatively bigger bills. Like all penguin species, the macaroni penguin, one of the fascinating animals starting with M, is flightless and has a streamlined body, with wings that are stiffened and flattened into flippers, perfectly adapted for life in the water.

Macaw

Macaws belong to a group of long-tailed, vividly colored parrots from the New World, classified under the tribe Arini. These birds are widely kept as pets and are popular in aviculture, though several species face conservation challenges in their natural habitats. Their diet is diverse, including seeds, nuts, fruits, palm fruits, leaves, flowers and stems. Vegetables that are safe for macaws to consume include asparagus, beets, bell peppers, broccoli, butternut squash, carrots, corn on the cob, dandelion greens, collard greens, hot peppers, spinach, sweet potatoes, tomatoes and zucchini.

MacGillivray’s Warbler

MacGillivray’s warbler (Geothlypis tolmiei), one of the fascinating animals that start with M, is a type of New World warbler. These birds are typically sluggish and stout, often staying close to the ground, except when they are singing. Adult MacGillivray’s warblers exhibit olive-green upperparts and dull yellow underparts. Males are characterized by their black heads and breasts, whereas females and juveniles have light gray heads. Both sexes feature distinctive broken white eye-rings.

Machaeroides

Machaeroides is an extinct genus of sabre-toothed mammals that lived during the Eocene epoch, approximately 56 to 34 million years ago. Its fossils have been primarily found in Wyoming, USA. Machaeroides belonged to the order Creodonta and the family Oxyaenidae, making it one of the earliest known sabre-toothed mammals.

Resembling a small, dog-sized saber-toothed cat, Machaeroides had a distinctively elongated skull and walked plantigrade, meaning it placed its entire foot on the ground while walking, similar to bears and humans. This unique predatory adaptation highlights the evolutionary experimentation with different hunting strategies among early mammals​.

Mackenzie Valley Wolf

The northwestern wolf (Canis lupus occidentalis), commonly referred to as the Mackenzie Valley wolf, Alaskan timber wolf, or Canadian timber wolf, is a subspecies of the gray wolf found in western North America. These wolves are among the largest subspecies. In British Columbia, Canada, the average weight for five adult females was 42.5 kg (93.6 lbs), with individual weights ranging from 38.6 to 45.4 kg (85 to 100 lbs). For ten adult males, the average weight was 51.7 kg (112.2 lbs), with weights ranging from 47.6 to 61.2 kg (105 to 135 lbs). Overall, adult northwestern wolves typically weigh between 38.6 and 61.2 kg (85 to 135 lbs).

Macrauchenia

Macrauchenia, meaning “long llama” from the Greek “big neck” (originally named from the now-invalid genus Auchenia), is an extinct genus of large ungulates that lived in South America from the late Pliocene to the end of the Pleistocene. This animal possessed a camel-like body structure, with robust legs, a lengthy neck and a relatively small head. However, its feet were more akin to those of a modern rhinoceros, featuring one central toe flanked by two side toes on each foot.

Macrauchenia, one of the fascinating animals that start with M, was a sizeable creature, measuring approximately 2.5–3 meters (8.2–9.8 feet) in length and standing about 1.8 meters (5.9 feet) tall at the shoulder. It weighed between 909 and 1,000 kilograms (2,004–2,205 pounds), comparable in size to a black rhinoceros.

Madagascar Hissing Cockroach

The Madagascar hissing cockroach (Gromphadorhina portentosa), commonly referred to as the hissing cockroach or hisser, ranks among the largest cockroach species, growing to a length of 5 to 7.5 centimeters (2 to 3 inches) when fully mature. These insects are native to Madagascar, an island off the coast of Africa, where they are typically found in decaying logs. They belong to a group of around 20 known species of sizable hissing roaches from Madagascar, many of which are popular as pets.

The Madagascar hissing cockroach, one of the fascinating animals that start with M, has made appearances in Hollywood films. Notably, in the 1975 movie Bug, they were depicted as cockroaches capable of starting fires by rubbing their legs together. In the 1977 film Damnation Alley, they were portrayed as post-nuclear-war mutant, armor-plated “killer” cockroaches. Additionally, in the sci-fi satire Starship Troopers, set in a future where humans are at war with an alien species called “The Bugs,” a teacher is shown urging her students to stomp on these cockroaches during a TV propaganda broadc

Madagascar Jacana

The Madagascar Jacana (Actophilornis albinucha) is a unique bird endemic to Madagascar, primarily inhabiting freshwater wetlands, marshes and ponds. This species is characterized by its long toes and claws, which allow it to walk on floating vegetation without sinking, a crucial adaptation for its wetland habitat.

The Madagascar Jacana, one of the fascinating animals that start with M, is an omnivorous bird, feeding on a variety of aquatic and terrestrial prey, including insects, small crustaceans, tadpoles and seeds. Notably, the species exhibits an interesting breeding behavior where males take on the primary role of nest-building and caring for the eggs and chicks, which is relatively uncommon among birds.

Madagascar Tree Boa

Sanzinia madagascariensis, commonly known as the Madagascar tree boa or Malagasy tree boa, is a boa species native to Madagascar. Adult boas typically measure between 4 to 5 feet (122 to 152 cm) in length, although individuals reaching 6 to 7 feet (183 to 213 cm) are not rare. These boas have thermoreceptive pits situated between their labial scales. Females are generally larger than males. The species is greenish in color and predominantly found on the eastern side of Madagascar. In 2006, the IUCN Red List of Threatened Species classified this species as Vulnerable (VU) under the criteria A1cd (v2.3, 1994).

Madora Moth

The Madora Moth, scientifically known as Gonimbrasia belina, is an emperor moth native to southern Africa. Its large, edible caterpillar stage is commonly referred to as the mopane worm. These caterpillars primarily feed on the leaves of the mopane tree and are a significant protein source for many communities in the region. Adult Madora Moths are robust and do not feed, living only to mate before dying within a few days. The mopane worms are harvested extensively, often by hand and can be eaten dried, fried, or cooked with various ingredients, contributing to both subsistence and commercial economies in southern Africa.

Magellanic Penguin

The Magellanic penguin (Spheniscus magellanicus) is a species native to South America, primarily breeding along the coastal regions of Patagonia. These medium-sized penguins typically reach heights of 61 to 76 cm (24 to 30 inches) and weigh between 2.7 and 6.5 kg (6.0 to 14.3 lbs). Males are generally larger than females and both experience weight loss during the period when they are rearing their chicks.

Magellanic penguins, one of the fascinating animals that start with M, hunt in the ocean, feeding on small pelagic fish, hagfish, cuttlefish, squid, krill and other crustaceans, consuming sea water along with their prey. They possess a specialized salt-excreting gland that helps them eliminate excess salt from their bodies. Adult Magellanic penguins frequently dive to depths of 20 to 50 meters (66 to 164 feet) to capture their prey.

Maggot

A maggot is the larval stage of a fly, specifically within the order Diptera and is particularly associated with the larvae of Brachycera flies. Anglers frequently use commercially supplied maggots as bait to catch non-predatory fish, making them the most popular bait among European anglers. Historically, live maggots from certain fly species have been used for wound cleaning, a practice dating back to ancient times. The larvae of Lucilia sericata, a type of calliphorid fly, are notably utilized for this purpose.

However, like fleas and ticks, maggots can pose a significant threat to pets and livestock, especially sheep. During the summer, flies reproduce quickly, leading to large numbers of maggots. This can result in infestations and a heightened risk of myiasis, where living tissue becomes infested with maggots, affecting sheep and other animals.

Magnolia Warbler

The magnolia warbler, one of the fascinating animals that start with M, resides in the northern regions of several Midwestern states and the far northeastern areas of the United States, with Minnesota and Wisconsin marking its southernmost range. This moderately small New World warbler measures between 11 and 13 cm (4.3 to 5.1 inches) in length, with a wingspan of 16 to 20 cm (6.3 to 7.9 inches).

Adult birds typically weigh between 6.6 and 12.6 grams (0.23 to 0.44 ounces), although some individuals have been recorded weighing up to 15 grams (0.53 ounces) before migration. The magnolia warbler is classified as least concern on the IUCN Red List due to its widespread presence and commonality within its habitat, indicating it is not currently at risk of extinction.

Magpie

Magpies, belonging to the crow family (Corvidae), are easily recognizable with their striking black-and-white plumage and long, diamond-shaped tails. They are native to Europe, Asia and North America, with the Eurasian magpie (Pica pica) being particularly well-known. Magpies are highly intelligent birds, exhibiting behaviors such as tool use and complex social interactions.

They are omnivorous, feeding on a varied diet that includes insects, small animals, fruits and seeds. Magpies are also known for their chattering calls and the ability to mimic other sounds. They build large, domed nests and are known for their “funeral” behavior, where they gather and call loudly around a deceased magpie​.

Magyarosaurus

Magyarosaurus, meaning “Magyar lizard,” is a genus of dwarf sauropod dinosaur that lived during the late Cretaceous Period (early to late Maastrichtian) in what is now Romania. This sauropod was relatively small, measuring about 6 meters (20 feet) in length and weighing between 750 and 1,000 kilograms (1,650 to 2,200 pounds). Its diminutive size is a unique characteristic, as none of its close relatives were as small. Additionally, Magyarosaurus is distinguished by the presence of dermal armor.

Mahi Mahi

The mahi-mahi, also known as the common dolphinfish (Coryphaena hippurus), is a ray-finned fish that inhabits surface waters in off-shore temperate, tropical and subtropical regions around the globe. These fish are characterized by their compressed bodies and a singular, elongated dorsal fin that stretches from their head to near the tail fin.

Mature males are noted for their distinctive “foreheads,” which grow and protrude significantly above the body as they age, shaped by the strong musculature of their backs. This feature is sexually dimorphic, as females possess a more rounded head. Mahi-mahi is primarily consumed in the United States and Caribbean nations, although its popularity is steadily rising in many European countries.

Maiasaura

Maiasaura, one of the fascinating animals that start with M, is a genus of large, herbivorous saurolophine hadrosaurid dinosaurs, commonly known as “duck-billed” dinosaurs. They inhabited the region now known as Montana, USA and Alberta, Canada, during the Upper Cretaceous Period (mid to late Campanian), approximately 86.3 to 70.6 million years ago. Maiasaura peeblesorum individuals were substantial in size, reaching up to 9 meters (30 feet) in length and weighing around 4 metric tons (4.4 short tons). These dinosaurs featured a pronounced “duck-billed” mouth and had rows of hundreds of teeth, a characteristic trait of hadrosaurids. Their post-cranial anatomy was quite similar to other hadrosaurids.

Maine Coon

The Maine Coon is a large breed of domesticated cat and one of the oldest natural breeds in North America. Originating from the U.S. state of Maine, it holds the title of the official state cat. Known for its substantial size and sociable nature, the Maine Coon has earned the nickname “the gentle giant.” This breed is distinguished by its dense fur coat, which provides protection against Maine’s harsh climate and its “dog-like” qualities.

The first literary mention of the Maine Coon was in Frances Simpson’s The Book of the Cat (1903). Typically, male Maine Coons weigh between 18 to 22 pounds (8.2 to 10.0 kg), while females range from 12 to 15 pounds (5.4 to 6.8 kg). Adult Maine Coons can stand between 10 and 16 inches (25 to 41 cm) tall and reach lengths of up to 38 inches (97 cm), including their long, tapering and heavily furred tails, which can grow up to 14 inches (36 cm) and resemble a raccoon’s tail. Curious for more? Read the full article here!

Mako Shark

Mako shark is known as the largest types of sharks as well as the true apex predator of the ocean, which thrive in the diverse environment of ocean. This shark has been classified into two species, the Shortfin Mako (Isurus oxyrinchus) and the Longfin Mako (Isurus paucus). Their scientific name is “Isurus”, which means “equal tail”, however, the other names of Mako are bonito sharks and sometimes blue pointers.

 They have very distinct features as compared to other sharks, such as incredible speed, powerful, long, and sleek, streamlined bodies with the title of fastest swimming sharks. Their speed is truly incredible as they can even compete blue whale, Great white shark and killer whale, that’s why they are credited as fastest fish in the ocean. Curious for more? Read the full article here!

Mal Shi

The Mal-Shi, a charming hybrid breed, is a cross between a Maltese and a Shih Tzu. Known for its affectionate, playful and friendly nature, the Mal-Shi is a popular choice for families and individuals alike. These small dogs typically weigh between 6 to 12 pounds and stand around 10 inches tall. They are characterized by their long, silky coats, which can come in a variety of colors including white, black and brown. Regular grooming is essential to keep their coats healthy and free of mats.

Mal-Shis, one of the fascinating animals that start with M, are well-suited for apartment living due to their moderate exercise needs, which can be met with daily walks and indoor play. They are highly trainable and respond well to positive reinforcement. Additionally, their social nature makes them great companions for children and other pets. While generally healthy, they can be prone to dental and respiratory issues inherited from their parent breeds​.

Malayan Civet

The Malayan civet (Viverra tangalunga), also referred to as the Malay civet or Oriental civet, is a viverrid species native to the Malay Peninsula, as well as the islands of Sumatra, Bangka, Borneo, the Riau Archipelago and the Philippines. The IUCN classifies it as “Least Concern” due to its widespread distribution, adaptability to degraded habitats and presence in numerous protected areas. The Malayan civet features a tail that is black on the upper side and ringed underneath. This species is found in higher densities in unlogged forests compared to logged ones, with fruit constituting a larger portion of its diet in pristine forests.

Malayan Krait

Bungarus candidus, commonly known as the Malayan krait or blue krait, is an extremely venomous snake species. This snake can reach a total length of 108 cm (43 inches), including a tail length of 16 cm (6.3 inches). The dorsal side features 27 to 34 dark-brown, black, or bluish-black crossbands that extend across the body and tail, tapering and rounding on the sides. The first crossband merges seamlessly with the dark color of the head. These dark bands are separated by wide, yellowish-white interspaces that may be speckled with black. The ventral side is uniformly white.

Malayan Tiger

The Malayan tiger, one of the fascinating animals that start with M, is a distinct population of the Panthera tigris tigris subspecies, found in Peninsular Malaysia. This population resides primarily in the southern and central regions of the Malay Peninsula and is currently classified as critically endangered. As of April 2014, there were an estimated 80 to 120 mature individuals, with numbers continuing to decline.

Measurements of 11 male and 8 female Malayan tigers show that males average 8 feet 6 inches (259 cm) in length, while females average 7 feet 10 inches (239 cm). In the State of Terengganu, the body lengths of 16 female tigers ranged from 70 to 103 inches (180 to 260 cm), with an average of 80.1 inches (203 cm). Their heights varied between 23 and 41 inches (58 to 104 cm) and their body weights ranged from 52 to 195 pounds (24 to 88 kg).

Malchi

The Malchi, one of the fascinating animals that start with M, is a designer dog breed, a mix between a Maltese and a Chihuahua, known for its affectionate and lively personality. These small dogs typically weigh between 5 to 12 pounds and stand about 12 inches tall. Malchis are known for their spunky nature and can be quite vocal, making them good watchdogs but sometimes excessive barkers. They are best suited for families with older children or without children, as their small size makes them prone to accidental injuries.

Mallard

The mallard, also known as the wild duck (Anas platyrhynchos), is a species of dabbling duck that inhabits temperate and subtropical regions across the Americas, Eurasia and North Africa. The mallard measures between 50 and 65 cm (20 to 26 inches) in length, with the body accounting for roughly two-thirds of this length. Its wingspan ranges from 81 to 98 cm (32 to 39 inches) and the bill measures between 4.4 and 6.1 cm (1.7 to 2.4 inches).

The mallard is typically slightly heavier than other dabbling ducks, weighing between 0.7 and 1.6 kg (1.5 to 3.5 lbs). Mallards thrive in wetlands, feeding on aquatic plants and small animals and are known for their social behavior, often gathering in groups or flocks of varying sizes.

Malteagle

The Malteagle, a charming hybrid between the Beagle and Maltese, is known for its friendly and inquisitive nature. These small dogs have large personalities and thrive on human companionship, making them great family pets. Malteagles are energetic and require daily exercise, such as walks and playtime, to stay healthy and happy. They typically get along well with other pets if socialized early and are especially good with children due to their gentle demeanor.

Regular grooming is essential to maintain their often silky coat, which can be prone to tangling. This breed is well-suited for various living environments, including apartments, as long as they receive adequate physical activity and mental stimulation​.

Maltese

The Maltese dog, one of the fascinating animals that start with M, refers to both an ancient breed of small, white-coated dogs originating from Italy, often linked with the island of Malta. The contemporary Maltese boasts a silky, pure-white coat, drooping ears, a tail that curls over its back. Notably, this breed does not shed.

Primarily kept for companionship, decorative purposes, or competitive showing, the Maltese features a dense, glossy and silky coat that falls smoothly along the body without curls or an undercoat. While the coat is predominantly pure white, a slight ivory tint or light brown spots are acceptable. Adult Maltese dogs usually weigh between 3 to 4 kg (7 to 9 lbs). Females stand about 20 to 23 cm (8 to 9 inches) tall, with males being slightly taller. Known for their lively, calm and affectionate disposition, Maltese dogs, like other white-coated breeds, can develop tear stains.

Maltese Mix

A Maltese Mix is a hybrid dog breed resulting from crossing a Maltese with other breeds, producing a variety of adorable and charming dogs. Common mixes include the Maltipoo (Maltese and Poodle), known for being intelligent and hypoallergenic and the Morkie (Maltese and Yorkshire Terrier), which is small, energetic and playful. Another popular mix is the Malshi (Maltese and Shih Tzu), recognized for its sweetness and low-shedding coat. These mixes inherit various traits from their parent breeds, often making them affectionate, friendly and great companions for families and individuals alike​.

Maltese Shih Tzu

The Maltese Shih Tzu, also known as the Malshi, is a charming and affectionate hybrid breed, combining the best traits of the Maltese and Shih Tzu. Known for their friendly and adaptable nature, Malshis thrive in various living environments, from small apartments to large homes, as long as they receive ample love and attention. They typically have a long, silky coat that can come in colors like white, cream and gold, often considered hypoallergenic due to their low shedding, making them suitable for allergy sufferers​.

Malshis are energetic and playful but also enjoy cuddling and being lapdogs. They require regular grooming to prevent tangles and mats and their exercise needs are moderate, with daily walks and playtime sufficing. Health-wise, they can be prone to conditions like brachycephalic respiratory syndrome, patellar luxation and white shaker syndrome, so regular vet checkups are essential. With proper care, Malshis can live a long, healthy life, typically ranging from 12 to 14 years​.

Maltipom

The Maltipom, a crossbreed between the Maltese and the Pomeranian, is a small and affectionate dog known for its charming and fluffy appearance. Typically weighing between 4 to 10 pounds and standing 8 to 12 inches tall, Maltipoms inherit a mix of physical traits from their parent breeds, often showcasing a silky, long coat that requires regular grooming to prevent tangles and matting. These dogs are well-suited for various living conditions, including apartments and they thrive on regular exercise and mental stimulation. Maltipoms, one of the fascinating animals that start with M, are generally good with children and other pets, though supervision is necessary due to their small and delicate build.

Maltipoo

Maltipoos, a popular crossbreed between Maltese and Poodle parents, combine the desirable traits of both breeds to create an affectionate and intelligent companion dog. Known for their hypoallergenic coat, Maltipoos often inherit the low-shedding quality of Poodles and the gentle demeanor of Maltese, making them suitable pets for individuals with allergies or those seeking a low-maintenance grooming routine.

These dogs typically exhibit a friendly and outgoing personality, thriving in various living environments from apartments to larger homes, provided they receive adequate exercise and mental stimulation. Maltipoos, one of the fascinating animals that start with M, are recognized for their adaptability and social nature, forming strong bonds with their families and often displaying a playful demeanor that endears them to both children and adults alike.

Mamba

Mambas are swift, highly venomous snakes. Among the four species, the three green mambas are primarily arboreal, while the black mamba is mostly ground-dwelling. All species are active hunters during the day, feeding on birds, lizards and small mammals. As night falls, some species, particularly the terrestrial black mamba, retreat to a shelter.

Black mambas inhabit the savannas and rocky hills of southern and eastern Africa. They hold the title of Africa’s longest venomous snake, capable of reaching lengths up to 14 feet, though the average is around 8.2 feet. Additionally, they are among the world’s fastest snakes, capable of slithering at speeds up to 12.5 miles per hour.

Mamushi Snake

Gloydius blomhoffii, commonly known as the mamushi, Japanese moccasin, Japanese pit viper, Qichun snake, Salmusa, or Japanese mamushi, is a venomous pit viper species native to Japan. Adult mamushis typically measure between 45 and 81 cm (17.75 to 31.88 inches) in length, with the longest recorded individual reaching 91 cm (36 inches).

Their body features a pale gray, reddish-brown, or yellow-brown base color, adorned with a series of irregular lateral blotches outlined in black and often having lighter centers. The head is dark brown or black with beige or pale-gray sides.

Man of War Jellyfish

The Man of War jellyfish, known scientifically as Physalia physalis, is a marine creature infamous for its striking appearance and potent sting. Despite resembling a single organism, it is actually a colony of specialized polyps working together. This jellyfish is characterized by its vibrant blue or purple gas-filled float, which sits above the water and can reach up to 30 centimeters in length, aiding in both flotation and propulsion.

Below the float, long tentacles trailing up to 10 meters contain thousands of nematocysts, or stinging cells, used to capture prey and defend against predators. Encounters with the Man of War can result in painful and potentially dangerous stings, as its venom is capable of causing severe reactions in humans, including intense pain, welts and, in rare cases, systemic effects.

Manatee

Manatees, often referred to as sea cows, are large, fully aquatic marine mammals that primarily feed on vegetation. These gentle giants typically weigh between 400 and 550 kg (880 to 1,210 lbs) and measure around 2.8 to 3.0 meters (9 feet 2 inches to 9 feet 10 inches) in length, though some individuals can reach up to 4.6 meters (15 feet 1 inch) and weigh as much as 1,775 kg (3,913 lbs). Female manatees are generally larger and heavier than their male counterparts. Newborn manatees weigh approximately 30 kg (66 lbs) each at birth. Unique to female manatees are two teats located under each flipper, a trait that has historically linked them to elephants.

Manchester Terrier

The Manchester Terrier, one of the fascinating animals that start with M, is a smooth-haired terrier breed originally developed in the 19th century for vermin control, particularly rats, a task at which it excelled. Its proficiency made it a frequent participant in rat-baiting pits until the sport, outlawed in the UK since 1835, eventually faded away in the early 20th century.

Unlike some terrier breeds that are often described as “stoic and dour,” the Manchester Terrier is known for its intelligence and curiosity. This breed is characterized by its feisty and affectionate nature, as well as its courage and toughness, making it a loyal and eager-to-please companion.

Mandarin Rat Snake

The Mandarin Rat Snake, scientifically known as Euprepiophis mandarinus, is a striking species native to East Asia, particularly found in regions of China and Taiwan. Known for its vibrant and distinctive coloration, this non-venomous snake exhibits a predominantly green body marked with vivid orange or red stripes running longitudinally along its back.

Its slender build and agile movement make it well-suited for its arboreal lifestyle, often found in forested areas and near water sources where it preys upon small rodents, birds and occasionally amphibians. Despite its beauty, the Mandarin Rat Snake can be reclusive and is known to exhibit defensive behavior when threatened, coiling and vibrating its tail as a warning.

Mandrill

The mandrill (Mandrillus sphinx) is a large species of Old World monkey indigenous to west-central Africa. Known for being one of the most vividly colored mammals, it boasts red and blue skin on its face and rump. The mandrill has a robust body, a large head with a prominent muzzle and a short, stubby tail. Its limbs are proportionally sized, with fingers and toes that are more elongated compared to baboons. Additionally, it possesses a highly opposable big toe. Notably, the mandrill is the most sexually dimorphic primate and holds the title of the largest monkey species.

Maned Wolf

The maned wolf (Chrysocyon brachyurus) is a large canid native to South America, found in Argentina, Brazil, Bolivia, Peru and Paraguay and nearly extinct in Uruguay. Although its markings resemble those of foxes, it is neither a fox nor a wolf. As the largest canid in South America, the maned wolf stands up to 110 cm (43 in) at the withers and weighs between 20 and 30 kg (44–66 lb).

It is characterized by its long, slender legs and dense reddish coat, giving it a unique appearance. The maned wolf holds the title of the tallest wild canid, with its long legs likely adapted for navigating the tall grasslands of its habitat. Its fur ranges from reddish-brown to golden orange on the sides, complemented by long, black legs and a distinctive black mane.

Mangrove Snake

The Mangrove Snake, scientifically known as Boiga dendrophila, is a highly adaptable species found throughout Southeast Asia, including coastal regions of Thailand, Malaysia and Indonesia. This slender snake is recognized for its striking appearance, characterized by a glossy body that ranges in color from yellow or orange to black, often adorned with crossbands or irregular spots that provide effective camouflage in its mangrove and forest habitats.

In the face of its vibrant appearance, the Mangrove Snake is mildly venomous, using its rear-fanged teeth to subdue small prey such as birds, rodents and amphibians. Its arboreal nature and exceptional climbing abilities allow it to navigate dense vegetation and ambush unsuspecting prey from above.

Mangrove Snapper

The mangrove snapper, also known as the gray snapper (Lutjanus griseus), is a snapper species found in the western Atlantic Ocean, ranging from Massachusetts to Brazil, including the Gulf of Mexico, Bermuda and the Caribbean Sea. Typically, its color is a grayish red, though it can vary from bright red to copper red. When viewed from above while underwater, a dark stripe can be seen running across its eye. This species can grow up to 89 cm (35 inches) in length, although most individuals are under 40 cm (16 inches). The heaviest recorded weight for a mangrove snapper is 20 kg (44 lbs).

Manta Ray

Manta rays, one of the fascinating animals that start with M, are large rays classified under the genus Mobula. These rays are characterized by their broad heads, triangular pectoral fins and distinctive horn-shaped cephalic fins on either side of their mouths. They possess horizontally flattened bodies with eyes positioned on the sides of their heads, just behind the cephalic fins and gill slits located on their ventral surfaces. Their tails are short and lack skeletal support and they have small dorsal fins at the base of their tails. Manta rays can weigh up to 1,350 kg (2,980 lbs).

For both species, the width is approximately 2.2 times the body length. The species M. birostris can reach widths of at least 7 meters (23 feet), while M. alfredi typically grows to about 5.5 meters (18 feet). Their skin is coated in a layer of mucus and they usually exhibit a “chevron” pattern in their coloration.

Mantella Frog

The Mantella Frog, belonging to the genus Mantella, is a group of small, brightly colored amphibians native to Madagascar. Known for their vibrant hues of red, orange, yellow and blue, these frogs exhibit aposematic coloration, warning potential predators of their toxicity.

Despite their striking appearance, Mantella Frogs are not poisonous but sequester toxic alkaloids from their diet of ants and other arthropods, making them unpalatable to predators. They inhabit a variety of habitats including rainforests, swamps and montane forests, often near freshwater sources where they breed during the rainy season. Their diet consists primarily of small invertebrates and they play a crucial role in their ecosystem as both predator and prey.

Marabou Stork

The marabou stork (Leptoptilos crumenifer) is a sizable wading bird belonging to the stork family, Ciconiidae and is native to sub-Saharan Africa. This species breeds in both wet and dry environments, frequently found near human settlements, particularly around landfill sites. Nicknamed the “undertaker bird,” it gets this moniker from its rear view: cloak-like wings and back, slender white legs and occasionally a large white tuft resembling hair.

The marabou stork boasts the largest wingspan of any land bird, averaging 2.6 meters (8.5 feet), with some individuals recorded reaching up to 3.2 meters (10 feet).

Marans Chicken

The Marans Chicken, originating from the town of Marans in France, is renowned for its rich, dark brown eggs and robust, rustic appearance. This breed, classified as a dual-purpose chicken, is prized not only for its egg-laying abilities but also for its flavorful meat. Marans Chickens typically have a medium build with feathers ranging from dark copper to black, often exhibiting feathered legs and a calm disposition.

The Marans Chickens, one of the fascinating animals that start with M, thrive in free-range environments where they can forage and exhibit natural behaviors, contributing to their reputation as excellent backyard chickens. The unique dark brown eggs, ranging from deep chocolate to reddish hues, are a result of a specific genetic trait inherited from their French heritage.

Marble Fox

The Marble Fox, a unique color morph of the red fox (Vulpes vulpes), is characterized by its strikingly beautiful coat pattern. This variant, also known as the Arctic Fox in some regions, exhibits a blend of black and white fur with intricate marbling patterns that vary from individual to individual. Native to northern parts of North America, particularly in regions of Alaska and Canada, Marble Foxes possess adaptations suited to cold climates, including thick fur and compact bodies that conserve heat. They are predominantly carnivorous, feeding on small mammals, birds and sometimes scavenging for plant material.

Maremma Sheepdog

The Maremmano-Abruzzese Sheepdog, also known by various names such as the Maremmano, Maremma Sheepdog, or Abruzzese Sheepdog (Italian: pastore abruzzese), is an Italian breed renowned for its role as a livestock guardian dog. This breed is characterized by a robust, muscular physique, a dense white coat, a large head and a black nose. Males typically weigh between 35 and 45 kg and stand 65 to 73 cm at the shoulder, while females weigh between 30 and 40 kg and stand 60 to 68 cm tall. Some individuals can be significantly larger.

The coat is long, thick and coarse to the touch, forming a dense collar around the neck. The preferred color is solid white, though slight yellowing is permissible. The nose, lips and skin around the eyes are distinctly black.

Margay

The margay (Leopardus wiedii) is a small wild cat native to Central and South America. Known for being solitary and nocturnal, this felid predominantly inhabits primary evergreen and deciduous forests. Since 2008, it has been classified as Near Threatened on the IUCN Red List due to a declining population driven by habitat loss and deforestation.

In appearance, the margay closely resembles the larger ocelot (Leopardus pardalis), but with distinct differences such as a slightly shorter head, larger eyes and proportionally longer legs and tail. Margays weigh between 2.6 and 4 kg (5.7 to 8.8 lbs) and have a body length ranging from 48 to 79 cm (19 to 31 inches), with a tail length of 33 to 51 cm (13 to 20 inches). Uniquely among most cat species, female margays have only two teats.

Marine Iguana

The margay (Leopardus wiedii) is a small wild cat found in Central and South America. This solitary and nocturnal feline primarily inhabits primary evergreen and deciduous forests. It has been classified as Near Threatened on the IUCN Red List since 2008, with its population declining due to habitat loss and deforestation.

The marine iguana (Amblyrhynchus cristatus), also known as the sea iguana, saltwater iguana, or Galápagos marine iguana, is an iguana species endemic to the Galápagos Islands in Ecuador. Unique among lizards, marine iguanas spend part of their time in the ocean. Large males dive to forage for food, while females and smaller males feed in the intertidal zone during low tide. They typically live in colonies on rocky shores, where they bask after venturing into the cold water or intertidal zone, but they can also be found in marshes, mangrove swamps and on beaches.

Marine Toad

The cane toad (Rhinella marina), also known as the giant neotropical toad or marine toad, is a large, terrestrial toad native to South and mainland Central America. It is the largest species in the Bufonidae family. Female cane toads are notably larger than males, typically measuring between 10 and 15 cm (4 to 6 inches), with some individuals reaching up to 24 cm (9.4 inches). Larger specimens are often found in areas with lower population density. In the wild, cane toads have a lifespan of 10 to 15 years, but they can live much longer in captivity, with one known to have lived for 35 years.

Markhor

The markhor (Capra falconeri) is a large wild goat species native to South Asia and Central Asia, primarily found in Pakistan, India, the Karakoram range, parts of Afghanistan and the Himalayas. Since 2015, it has been listed as Near Threatened on the IUCN Red List. Markhors, one of the fascinating animals that start with M, stand 65 to 115 centimeters (26 to 45 inches) at the shoulder, measure 132 to 186 centimeters (52 to 73 inches) in length and weigh between 32 to 110 kilograms (71 to 243 pounds). Their coats vary from grizzled light brown to black, remaining smooth and short during the summer and growing longer and thicker in the winter.

Marmoset

Most marmosets, one of the fascinating animals that start with M, measure approximately 20 cm (8 inches) in length. Compared to other monkeys, they exhibit several seemingly primitive characteristics, such as having claws instead of nails and possessing tactile hairs on their wrists. Notably, they lack wisdom teeth and their brain structure is considered relatively basic. Their body temperature is unusually variable, fluctuating by up to 4°C (7°F) within a single day.

Native to South America, marmosets are found in countries including Bolivia, Brazil, Colombia, Ecuador, Paraguay and Peru. These highly active primates dwell in the upper canopy of forest trees, where they consume a diet of insects, fruits, leaves, tree sap and gum. Their long lower incisors enable them to gnaw holes in tree trunks and branches to access the gum inside, with some species being particularly specialized in gum feeding.

Marmot

Marmots, belonging to the genus Marmota, are large ground squirrels comprising 15 species found across Asia, Europe and North America. These herbivorous animals are active during the summer months and are often seen in groups. However, they remain unseen during the winter as they hibernate underground. Marmots hold the distinction of being the heaviest members of the squirrel family. Their total length typically ranges from 42 to 72 cm (17 to 28 inches) and their body mass averages around 2 kg (4.5 lbs) in spring for the smaller species, increasing to about 8 kg (18 lbs) in autumn. In larger species, their weight can sometimes exceed 11 kg (24 lbs).

Marsh Frog

The marsh frog (Pelophylax ridibundus) is a species of water frog indigenous to Europe and parts of western Asia. It is the largest frog species in most of its habitat, with males reaching around 100 mm (3.9 inches) in snout-vent length (SVL), while females typically grow slightly larger, up to 4 inches (SVL). This species exhibits a wide range of colors and patterns, from dark green to brown or gray, often featuring lighter green lines and usually a lighter stripe along the back. In early spring, marsh frogs tend to be darker in color to better absorb heat.

Marsican Brown Bear

The Marsican brown bear (Ursus arctos arctos, formerly known as Ursus arctos marsicanus), also referred to as the Apennine brown bear, is a unique subspecies of brown bear. These bears lead solitary lives and their population is critically low, with only about 50 individuals remaining in the Parco Nazionale d’Abruzzo, Lazio e Molise. They possess distinct characteristics that set them apart from other brown bear subspecies.

In terms of behavior, the Marsican brown bear exhibits patterns typical of brown bears. They are primarily nocturnal, except during mating season or when caring for their cubs, during which they demonstrate a notable degree of independence and self-sufficiency. Their mating season occurs from May to July, leading to cub births in early winter. Each February, females give birth to one to three cubs, which weigh less than 500 grams (18 oz) at birth and are highly dependent on their mother’s size for survival.

Masiakasaurus

Masiakasaurus, one of the fascinating animals that start with M, is a genus of small predatory noasaurid theropod dinosaurs that lived during the Late Cretaceous period in Madagascar. One of the most notable features of Masiakasaurus is its forward-projecting, or procumbent, front teeth. These teeth are heterodont, meaning they vary in shape along the jaw. The first four teeth in the lower jaw extend forward, with the first tooth angled just 10° above the horizontal. These teeth are elongated and spoon-shaped with hooked edges.

The forward-projecting teeth of Masiakasaurus were likely adapted for grasping small prey, making them ineffective for tearing larger food items apart. Additionally, at the front of the jaws, the carinae are limited to the base of the teeth, further suggesting that these teeth were not used for tearing prey.

Masked Angelfish

Genicanthus personatus, commonly known as the masked angelfish, is a species of marine ray-finned fish. This marine angelfish is predominantly bright white throughout its life stages. Juveniles exhibit a prominent black area covering most of their heads. As they mature, this black coloration begins to change, starting with the lips, which turn a bluish-white and the caudal fins that gradually darken to black.

When they reach a length of 15 to 18 centimeters (5.9 to 7.1 inches), some individuals may transition to males. During this sex change, they acquire vivid orange-yellow pigmentation on the pectoral fins, face and the edges of the dorsal, anal and pelvic fins. Additionally, males develop long, filamentous extensions on their caudal fin lobes.

Masked Palm Civet

The masked palm civet (Paguma larvata), also known as the gem-faced civet or Himalayan palm civet, is a species of viverrid found in the Indian subcontinent and Southeast Asia. Since 2008, it has been classified as Least Concern on the IUCN Red List. The masked palm civet’s fur ranges from grayish to ochraceous, with black coloration on its head, shoulders and neck and blackish brown on its tail and feet.

The masked palm civet, one of the fascinating animals that start with M, features a distinctive white blaze on its forehead and white markings above and below the eyes that extend to the ears, forming a half-collar. Morphologically, the masked palm civet resembles other palm civets but lacks spots or stripes. Its tail is notably long, exceeding two-thirds the length of its head and body and it has two pairs of mammae.

Mason Bee

The Mason Bee, belonging to the genus Osmia, is a solitary bee known for its efficient pollination abilities and gentle nature. Unlike honeybees, Mason Bees are solitary nesters, with each female constructing and provisioning her own individual nest chamber. They are named for their habit of using mud or other materials to build partitions within their nesting cavities, hence the term “mason.” These bees are vital pollinators of fruit trees, flowers and various crops due to their thorough pollination techniques, which involve collecting pollen on their abdomens rather than on their hind legs like honeybees.

Massasauga

The Massasauga rattlesnake (Sistrurus catenatus) is a small and venomous pit viper native to North America, known for its distinctive appearance and behavior. Found primarily in wetland habitats, such as marshes, swamps and prairies across the Great Lakes region and parts of the Midwest and Ontario, Canada, this snake plays a crucial role in its ecosystem as both predator and prey. It typically grows between 45 to 75 centimeters in length and is characterized by a pattern of dark blotches on a lighter background, often resembling a chain-like pattern, hence its species name “catenatus,” which means chained or linked.

Mastador

The Mastador, a crossbreed between the Mastiff and the Labrador Retriever, combines the impressive size and strength of the Mastiff with the friendly and gentle demeanor of the Labrador. This hybrid dog breed is known for its large, muscular build, often weighing between 100 to 160 pounds and standing 25 to 36 inches tall at the shoulder. Mastadors typically inherit the Labrador’s short, dense coat that comes in various colors such as black, yellow, chocolate, or brindle, often with some white markings. They are renowned for their loyalty, intelligence and affectionate nature, making them excellent family pets and companions.

Mastiff

A mastiff, one of the fascinating animals that start with M, is a robust and formidable breed of dog. These dogs rank among the largest canines, featuring a short coat, a long, low-set tail and sizable feet. They possess a large, heavy skull with a broad and short muzzle (brachycephalic) and drooping, pendant-shaped ears. Historical records from Europe and Asia, dating back 3,000 years, depict mastiff-like dogs.

Traditionally, mastiffs have served as guard dogs, safeguarding homes and properties. However, their roles throughout history have also included hunting, participating in wars and engaging in blood sports such as fighting each other and other animals, including bulls, bears and even lions.

Mastiff Mix

Mastiff mixes, while not officially recognized breeds, offer a fascinating range of possibilities for dog lovers. The temperament and physical characteristics of these gentle giants depend entirely on the other breed in the mix. A Bullmastiff, for instance, combines the Mastiff’s size with the athleticism and guarding prowess of a Bulldog. In contrast, a Mastador, a Labrador Retriever mix, leans towards the Lab’s playful and social personality. Regardless of the mix,  Mastiff mixes tend to be larger than average dogs, requiring ample space and strong owners for leash walks. Their lifespan can vary based on the other breed, but generally falls between 7-12 years.

Mauzer

The Mauzer, a delightful designer dog, is a spunky mix between the elegant Maltese and the spirited Miniature Schnauzer. While not recognized by major kennel clubs like the AKC, these pups are gaining popularity for their affectionate personalities and adaptability. Their appearance can be a delightful surprise, with coats ranging from the long, flowing locks of the Maltese to the wiry, double coat of the Schnauzer. Colors can also be a fun guessing game, with possibilities including white, black, brown and even a brindle mix.

May Beetle

May beetles, also known as June bugs or July beetles depending on their regional emergence time, are fascinating creatures with a surprising lifecycle. These clumsy, buzzing beetles belong to the scarab beetle family, alongside their glamorous cousins, the dung beetles. May beetles themselves are vegetarians, feasting on leaves at night. But the real drama unfolds underground. Their larvae, nicknamed white grubs, are plump, C-shaped residents of the soil for two to three years. These grubs are the bane of gardeners, munching on roots and sometimes causing significant damage to lawns and crops.

Mayan Cichlid

Mayaheros urophthalmus, commonly referred to as the Mayan cichlid or Mexican mojarra, is a species of cichlid found in Middle America. This fish is native to the Atlantic slope of tropical Mesoamerica, with a range extending from eastern Mexico to Nicaragua. The species was first documented in Everglades National Park, Florida, in 1983 and has since become a prevalent nonindigenous fish in South Florida.

Mayan cichlids, one of the fascinating animals that start with M, inhabit a variety of environments including freshwater marshes, mangrove swamps, lakes, rivers, rocky shorelines, lagoons, estuaries and coastal islands. Adults tend to favor coastal lagoons and rivers and are capable of surviving in marine conditions.

Mayfly

Mayflies, often referred to as shadflies or fishflies in Canada and the upper Midwestern United States, exhibit ancestral features likely present in the earliest flying insects. These traits include long tails and wings that do not fold flat against the abdomen. Their immature stages, known as “naiads” or “nymphs,” are aquatic and inhabit freshwater environments. The presence of mayfly nymphs is an indicator of clean, unpolluted and highly oxygenated water.

Meagle

The Meagle, a spunky designer dog, is a captivating mix between the tenacious Beagle and the feisty Miniature Pinscher. While not recognized as a purebred by major kennel clubs, these energetic pups are winning hearts with their loyalty and playful personalities.

Their appearance is a delightful guessing game, with some Meagles inheriting the Beagle’s floppy ears and hound dog expression, while others favor the Min Pin’s sleek build and perky button ears. Their coats can be short and smooth like a Beagle’s, or sport the glossy, denser fur of a Min Pin. Colors can range from classic black and white to playful combinations of tan, brown and brindle.

Mealworm Beetle

The mealworm beetle, despite its seemingly bland name, leads a bit of a double life. As an adult, it’s a dark-colored, flightless beetle belonging to the Tenebrionidae family, which boasts over 20,000 species! But the mealworm beetle’s true claim to fame lies in its larval stage. This is where things get interesting. The larva, more commonly known as a mealworm, is a plump, segmented creature that’s become a staple food source for everything from pet lizards to research labs. Mealworms are prolific decomposers, happily munching on grains, decaying plant matter and even other insects.

Mealybug

Mealybugs, one of the fascinating animals that start with M, are unarmored scale insects that thrive in warm, moist environments. They exhibit sexual dimorphism: females resemble nymphs, with simplified morphology and no wings, although, unlike many female scale insects, they usually retain their legs and can move. Males, on the other hand, are smaller, gnat-like and possess wings. As members of the Hemiptera order, mealybugs undergo hemimetabolous development, meaning they do not experience complete metamorphosis.

Meerkat

The meerkat (Suricata suricatta), also known as the suricate, is a small mongoose native to southern Africa. It features a broad head, large eyes, a pointed snout, long legs and a thin, tapering tail. Its coat has a brindled pattern. The meerkat’s head-and-body length ranges from 24 to 35 cm (9.4 to 13.8 inches) and it typically weighs between 0.62 and 0.97 kg (1.4 and 2.1 lbs). The coat color varies from light grey to yellowish-brown, with alternating light and dark bands on the back. Adapted for digging, meerkats have specialized foreclaws and the ability to thermoregulate, which helps them endure their harsh, arid environment.

Megalania

Megalania (Varanus priscus) is an extinct species of giant monitor lizard that was part of the megafaunal assemblage in Australia during the Pleistocene epoch. It holds the title of the largest terrestrial lizard ever known, although estimates of its size are uncertain due to the fragmentary nature of the available remains. Recent research indicates that most specimens likely reached lengths of around 3 meters (9.8 feet) or more, excluding the tail, while the largest individuals may have exceeded 7 meters (23 feet) in length.

Megalochelys

Megalochelys, meaning “great turtle,” is an extinct genus of tortoises that existed from the Miocene to the Pleistocene epochs. Renowned for their immense size, they are the largest tortoises known, with the carapace of M. atlas reaching lengths exceeding 2 meters (6.5 feet). The genus was widespread, with its range extending from western India and Pakistan to the eastern regions of Sulawesi and Timor in Indonesia. It is believed that the island populations may represent distinct species.

Megalodon

Otodus megalodon, commonly referred to as megalodon, is an extinct species of giant mackerel shark that lived approximately 23 to 3.6 million years ago. One interpretation of its appearance suggests it was a robust-looking shark, possibly similar in build to the great white shark. However, its jaws were likely blunter and wider and its fins might have been thicker due to its massive size. Additionally, megalodon may have had a pig-eyed appearance, characterized by small, deep-set eyes.

Megamouth Shark

The megamouth shark (Megachasma pelagios) is a deepwater shark species known for its distinctive appearance, although much about it remains a mystery. The shark’s upper body is brownish-black, while its underside is white. It has an asymmetrical tail with a long upper lobe, reminiscent of the thresher shark. Inside its gill slits are finger-like gill rakers that help capture food. The megamouth shark, one of the fascinating animals that start with M, is a relatively poor swimmer, characterized by a soft, flabby body and the absence of caudal keels.

Megamouth sharks are quite large, capable of reaching lengths of up to 5.49 meters (18 feet). Mature males typically measure around 4 meters (13 feet) and females about 5 meters (16 feet). Some individuals have been reported to weigh as much as 1,215 kilograms (2,679 pounds). A study conducted in 2019 suggested that the maximum length of the megamouth shark could be up to 6 meters (20 feet).

Meganeura

Imagine a dragonfly the size of a crow, with a wingspan wider than a dinner plate. That’s the Meganeura, a prehistoric insect that dominated the skies during the Carboniferous period, roughly 300 million years ago. Nicknamed “giant dragonfly” for a reason, Meganeura belonged to the extinct family Meganeuridae, known for its colossal winged members. These weren’t the delicate damselflies of today;  their large size is believed to be linked to the high oxygen levels in Earth’s atmosphere at the time.

Fossils reveal wingspans reaching an impressive 2.5 feet (0.75 meters) – making them the largest known flying insects ever discovered. Their name, Meganeura, even translates to “large veins,” referencing the intricate network of veins that stiffened their expansive wings and helped them stay aloft.

Megatherium

Megatherium, one of the fascinating animals that start with M, is an extinct genus of ground sloths native to South America that thrived from the Early Pliocene period. It ranks among the largest ground sloths ever discovered, with an overall body length of approximately 6 meters (20 feet). Volumetric analysis indicates that a fully grown M. americanum likely weighed between 3,700 and 4,000 kilograms (8,200 to 8,800 pounds), making it comparable in size to an Asian elephant.

Meiolania

Meiolania, one of the fascinating animals that start with M, is an extinct genus of meiolaniid stem-turtles that inhabited Australasia for much of the Cenozoic era. These large turtles had shells measuring between 0.7 and 2 meters (2 feet 4 inches to 6 feet 7 inches) in length. Currently, four species of Meiolania are recognized, although the validity of two of these species is debated. Initially, Richard Owen described Meiolania as a species of lizard related to Megalania in the late 19th century. However, subsequent fossil discoveries confirmed that Meiolania was indeed a type of turtle.

Mekong Giant Catfish

The Mekong giant catfish, one of the fascinating animals that start with M, is a sizable and endangered species of catfish. Characterized by its grey to white color and absence of stripes, this species stands out from other large catfish in the river due to its almost complete lack of barbels and the absence of teeth. While juvenile Mekong giant catfish do possess barbels and oral teeth, these features gradually disappear as they mature and are no longer present once they reach a length of 30-50 cm.

Merganser

Mergansers are fascinating fish-eating ducks found in North America, Europe and Asia. These medium to large-sized ducks are known for their distinctive serrated bills, perfectly adapted for catching slippery fish. Unlike most ducks, mergansers have slender bodies and narrow bills with sawtooth-like edges that help them grip and hold onto their wiggling prey. Their keen eyesight allows them to spot fish from underwater and their powerful wings propel them through the water in pursuit.

Mexican Alligator Lizard

The Mexican alligator lizard (Abronia graminea), also referred to as the green arboreal alligator lizard, is an endangered species native to the Sierra Madre de Oaxaca highlands in Mexico. This lizard is characterized by its dorsoventrally flattened body, triangular head and weak lateral fold. It can grow up to 10.6 cm (4.2 inches) in snout-vent length and about 16.0 cm (6.3 inches) in tail length.

One specimen with a snout-vent length of 9.8 cm (3.9 inches) weighed 21.2 grams (0.75 ounces), while another measuring 10.0 cm (3.9 inches) weighed 20.7 grams (0.73 ounces). The species is equipped with a prehensile tail that can regenerate if lost, as well as long, strong limbs and digits suited for its arboreal lifestyle.

Mexican Black Kingsnake

The Mexican black kingsnake (Lampropeltis getula nigrita) is a member of the colubrid family and a subspecies of the common kingsnake, which herpetologists argue could include up to 10 distinct varieties. In their natural habitat, most kingsnakes grow to an average length of 90-120 centimeters (3–4.5 feet) and have a plump, stocky build. However, when kept in captivity, some kingsnakes can grow to exceed 1.5 meters (5 feet). This increased size is likely due to the consistent and abundant diet provided in captivity, which is often more reliable than what they would find in the wild. Adult Mexican black kingsnakes can weigh up to 1.3 kg (3 lbs) and their lifespan ranges from 20 to 30 years.

Mexican Eagle

There’s a fascinating duality to the term “Mexican Eagle.”  While the majestic Golden Eagle reigns supreme on the Mexican coat of arms and as the official national bird, the Crested Caracara also holds a special place in Mexican culture, sometimes being referred to as the “Mexican Eagle” as well.

The Golden Eagle, “águila real” in Spanish, is a powerful bird of prey known for its sharp eyesight and impressive hunting skills. Soaring high above mountains and deserts, it embodies the strength and resilience of Mexico. The Crested Caracara, on the other hand, is a scavenger and opportunistic hunter with a distinctive crest on its head.

Mexican Fireleg Tarantula

Brachypelma boehmei, commonly known as the Mexican fireleg or Mexican rustleg tarantula, is a species native to Guerrero state in Mexico. These tarantulas are known for their longevity and their preference for burrowing and hiding in dry scrubland environments. Like other tarantulas in their genus, they protect themselves with urticating hairs when threatened. The Mexican fireleg is visually similar to the Mexican redknee tarantula (Brachypelma hamorii, previously mistaken for Brachypelma smithi) due to its striking orange and black coloration. Adult Mexican firelegs typically measure between 5 to 6 inches in size.

Mexican Free-Tailed Bat

The Mexican free-tailed bat, also known as the Brazilian free-tailed bat (Tadarida brasiliensis), is a medium-sized bat species native to the Americas. These bats generally measure about 9 cm (3.5 inches) in length and weigh between 7 and 12 grams (0.25 to 0.42 ounces), with females typically being 1 to 2 grams heavier than males due to the need for additional fat reserves during gestation and nursing. Their tails, which extend beyond the uropatagium, account for nearly half of their total body length, earning them the name “free-tailed” bats.

Mexican Mole Lizard

The Mexican mole lizard (Bipes biporus), also known as the five-toed worm lizard or simply Bipes, is a species of amphisbaenian. This pink, worm-like creature measures between 18 and 24 cm (7.1 to 9.4 inches) in snout-to-vent length (SVL) and has a width of 6 to 7 mm (0.24 to 0.28 inches). It typically has a lifespan of one to two years. The Mexican mole lizard’s skin is segmented, giving it a corrugated appearance. Similar to earthworms, it moves underground through the peristaltic motion of its segments. Its blunt head is well-adapted for burrowing into sandy soils efficiently.

Microraptor

Microraptor is a genus of small, four-winged dromaeosaurid dinosaurs, with numerous well-preserved fossil specimens discovered in Liaoning, China. These fossils date back to the early Cretaceous period, specifically the Jiufotang Formation (Aptian stage), approximately 125 to 120 million years ago.

Microraptor, one of the fascinating animals that start with M, ranks among the smallest known non-avian dinosaurs, with the holotype of M. gui measuring 77 centimeters (2.53 feet) in length, boasting a wingspan of 88 to 94 centimeters (2.89 to 3.08 feet) and weighing between 0.5 to 1.4 kilograms (1.1 to 3.1 pounds). Larger specimens have been found, which would have reached at least 80 centimeters (2.6 feet) in length, with a wingspan exceeding 99 centimeters (3.25 feet) and weighed between 1.25 to 1.88 kilograms (2.8 to 4.1 pounds).

Midget Faded Rattlesnake

Crotalus concolor, commonly referred to as the midget faded rattlesnake, faded rattlesnake, or yellow rattlesnake, is a species of pit viper found in the western United States. Adult specimens generally range from 50 to 60 cm (20 to 24 inches) in length, but they can grow up to 75 cm (30 inches). This size is significantly smaller compared to the typical western rattlesnake, which can reach lengths of up to 126 cm (64 inches). The smallest gravid female recorded measured 52.2 cm (20.5 inches).

Miki

The Miki, pronounced Mee-Kee, is a charming and relatively rare toy breed developed in the United States during the 1980s. Bred from a blend of several popular small companions like the Shih Tzu, Maltese and Yorkshire Terrier, the Miki inherited a delightful mix of traits. These playful pups boast a long, silky coat that comes in a variety of colors and patterns and their floppy ears and expressive eyes add to their endearing look. Despite their small size, Mikis are known for their friendly and outgoing personalities. They are intelligent and eager to please, making them well-suited for training and even excelling in therapy or service dog roles.

Milk Snake

The milk snake (Lampropeltis triangulum), also known as the milksnake, is a species of kingsnake with 24 recognized subspecies. This species thrives in a variety of habitats, typically favoring forested regions and open woodlands.

Milk snakes exhibit considerable variation in size depending on the subspecies. They can range from as small as 14 inches (36 cm) to as large as 72 inches (183 cm) in length. In North America, wild adults typically weigh between 38 and 225 grams (1.3 to 7.9 ounces). However, exceptionally large individuals, usually found in captivity, can weigh between 750 and 1,400 grams (1.65 to 3.09 pounds).

Milkfish

The milkfish (Chanos chanos) is a prevalent species of ray-finned fish native to the Indo-Pacific region. While they can grow up to 1.80 meters (5 feet 11 inches), they are typically around 1 meter (39 inches) in length. Milkfish can weigh up to approximately 14 kilograms (31 pounds) and live up to 15 years. They possess an elongated, somewhat compressed body that is both symmetrical and streamlined. Key features include a single dorsal fin, falcate pectoral fins and a large, forked caudal fin.

Milkweed aphids

Aphis nerii, a member of the Aphididae family, is commonly known as the oleander aphid, milkweed aphid, sweet pepper aphid and nerium aphid. These aphids are notable for their viviparous reproduction, where females give birth to live young (nymphs). Female oleander aphids reproduce through parthenogenesis and while males have not been observed in the wild, they have been produced in laboratory settings. This aphid species is prevalent in areas with tropical and Mediterranean climates.

Millipede

Millipedes, one of the fascinating animals that start with M, belong to the class Diplopoda and are distinguished by having two pairs of jointed legs on most of their body segments. They exhibit a wide range of shapes and sizes, with lengths varying from as small as 2 mm (1/16 inch) to about 35 cm (14 inches). The number of segments can range from as few as eleven to over three hundred. Typically, millipedes are black or brown, although some species display bright colors, often as a warning signal indicating their toxicity.

Mini Labradoodle

The Mini Labradoodle is a social butterfly in the canine world, offering a delightful mix of intelligence, playfulness and hypoallergenic potential. These compact companions are a cross between the Labrador Retriever, known for its friendly and trainable nature and the Miniature Poodle, famous for its intelligence and allergy-friendly coat. Their size can vary a bit, typically standing around 14-16 inches tall and weighing between 10 and 30 pounds. This makes them a great choice for apartments or smaller homes.

Mini Lop

The Mini Lop, one of the fascinating animals that start with M, is a domestic rabbit breed officially recognized by the American Rabbit Breeders Association (ARBA). Originating from German Lops, which weigh around 8 pounds (3.6 kg) and are characterized by their large, slender bodies and thick ears, the Mini Lop was first bred in the United States by a promoter named Herschbach.

In 1972, he successfully bred the first Mini Lops by pairing an agouti lop with a white female lop. The initial offspring were solid-colored, but subsequent generations exhibited broken colors. Through selective breeding, the Mini Lop developed into a breed with high-quality standards.

Miniature Bull Terrier

The English Miniature Bull Terrier traces its origins to the now-extinct English White Terrier, along with the Dalmatian and Bulldog. These dogs have short, fine and glossy coats that lie close to the skin, similar to Bull Terriers. In show rings, they are accepted in white, white with another color, or fully colored, though blue or liver-colored coats are considered undesirable. Minimal grooming is required for their maintenance. Like their Bull Terrier relatives, Miniature Bull Terriers are affectionate and can exhibit typical terrier stubbornness. Nonetheless, they are excellent pets for individuals with limited living space.

Miniature Husky

The Miniature Husky, also sometimes called the Klee Kai, isn’t quite what it seems. Unlike most “miniature” versions of dog breeds, Miniature Huskies aren’t actually a direct descendant of the Siberian Husky. They are a separate breed altogether, developed in Alaska in the 1970s to resemble a smaller version of their husky cousins. Despite the independent origin, Miniature Huskies share some of the Siberian Husky’s hallmarks – a thick double coat with a variety of colors and markings, piercing blue or brown eyes and a playful, energetic spirit. However, true to their name, they come in a much smaller package, typically standing around 13-17 inches tall and weighing between 15 and 35 pounds.

Miniature Pinscher

The Miniature Pinscher, often called the Zwergpinscher or Mini Pin, is a small dog breed of the pinscher type that originated in Germany. This breed is known for its well-balanced, sturdy, compact and smooth-coated physique. Miniature Pinschers are naturally groomed, vigorous and highly alert.

They are characterized by their distinctive hackney-like gait, fearless demeanor, complete self-assurance and spirited presence. Their legs are straight, without any inward or outward bending. The breed is also prone to separation anxiety. Miniature Pinschers often have docked tails and cropped ears, although the AKC no longer mandates ear cropping for show dogs. Some individuals may also have naturally erect ears.

Mink

Mink, one of the fascinating animals that start with M, are dark-colored, semiaquatic, carnivorous mammals. In the wild, male minks weigh around 1 kg (2 lb 3 oz) and measure approximately 60 cm (23.5 in) in length. Farm-raised males can grow significantly larger, reaching up to 3.2 kg (7 lb 1 oz). Female minks typically weigh about 600 g (1 lb 5 oz) and measure around 50 cm (19.5 in) in length. These measurements exclude the tail, which ranges from 12.8 to 22.8 cm (5 to 9 in).

Wild minks possess a rich, glossy brown coat that appears silky. Farm-bred minks, however, exhibit a range of colors from white to almost black, mirroring the variation seen in British wild mink. Their fur is deep, rich brown with or without white spots on the underparts, comprising a dense, slick underfur topped with dark, glossy, almost stiff guard hairs.

Minke Whale

The minke whale, also known as the lesser rorqual, is a complex species of baleen whale. There are two recognized species: the common (or northern) minke whale and the Antarctic (or southern) minke whale. Minke whales are the second smallest among baleen whales, with only the pygmy right whale being smaller.

Males reach sexual maturity at around 7–8 years of age, typically measuring 8.35 meters (27.4 feet) in length and weighing about 7 metric tons (6.9 long tons; 7.7 short tons). Females at sexual maturity average 8.9 meters (29 feet) in length and 8.25 metric tons (8.12 long tons; 9.09 short tons) in weight. It is estimated that females can grow beyond 10 meters (33 feet) in length and weigh between 10–12 metric tons (9.8–11.8 long tons; 11–13 short tons).

Mississippi Kite

The Mississippi kite (Ictinia mississippiensis) is a small raptor belonging to the family Accipitridae. Known for their slender, pointed wings, these birds are adept fliers and often seem to glide effortlessly in the air, frequently seen circling in groups. Adult Mississippi kites are primarily gray, with darker gray tail feathers and outer wings, while their heads and inner wings are lighter in shade. Regardless of age, these kites feature red eyes and legs that range from red to yellow. Both males and females share a similar appearance, although males tend to have slightly paler heads and necks.

Moccasin Snake

The term “moccasin” refers to two different species of venomous snakes in the pit viper family: the cottonmouth (Agkistrodon piscivorus) and the Mexican moccasin (Agkistrodon bilineatus). These semi-aquatic vipers are found in the southern United States and northern Mexico, respectively.

Both moccasins are known for their large, triangular heads, thick bodies and short, blunt tails. They’ve earned the nickname “cottonmouth” due to their defensive threat display, where they gape their mouth wide, revealing the bright white lining – a stark warning to potential threats. While not the most aggressive snakes, moccasins will readily strike if they feel cornered or threatened.

Mockingbird

Mockingbirds, one of the fascinating animals that start with M, are New World passerine birds belonging to the family Mimidae. They are renowned for their ability to mimic the songs of other birds and the sounds of insects and amphibians, often performing these imitations loudly and in quick succession. Additionally, they are known for their extreme territorial behavior when protecting their hatchlings. Mockingbirds are opportunistic omnivores, consuming a diet that includes insects, fruits, seeds and sometimes greens. The northern mockingbird is the only species commonly found in North America.

Modern Game Chicken

The Modern Game chicken is a striking breed with a fascinating history. Developed in England during the 19th century, these birds weren’t bred for meat or eggs, but purely for show. Their ancestors were the fierce gamecocks used in cockfighting, but after the sport’s ban, breeders focused on creating an elegant exhibition bird. The result? A tall, slender chicken with an upright posture and a remarkably long neck and legs. Their bodies are surprisingly light, shaped a bit like a clothes iron and their feathers come in a wide variety of colors, from classic black and white to wheaten and even blue.

Mojarra

The mojarras, one of the fascinating animals that start with M, belong to the family Gerreidae within the order Perciformes. This family comprises approximately 53 species distributed globally in tropical and warm temperate regions. While they predominantly reside in coastal salt and brackish waters, some species are also found in freshwater environments. Identifying these species in the field can be challenging, often necessitating microscopic examination. Mojarras typically exhibit schooling behavior and are known to seek refuge in shallow coastal waters, likely as a strategy to evade large predators such as lemon sharks.

Mojave Ball Python

The Mojave Ball Python, a captivating resident of the reptile world, isn’t your typical ball python. Unlike its usual banded or “alien head” patterned relatives, the Mojave boasts a unique visual flair. Imagine a stunning patchwork quilt made of browns, tans and blacks, with a smattering of vibrant yellows for good measure. This is the signature Mojave “blanket,” where large, round blotches with dark centers replace the standard ball python markings. This mesmerizing design is a result of a genetic mutation, making each Mojave a one-of-a-kind masterpiece.

Mojave Rattlesnake

Crotalus scutulatus, commonly known as the Mohave Rattlesnake, typically reaches a total length (including the tail) of under 100 cm (3.3 ft). Males can grow up to 123.6 cm (4.1 ft), while females reach a maximum length of 92.2 cm (3.0 ft). The Mohave Rattlesnake is classified as Least Concern (LC) on the IUCN Red List of Threatened Species (v3.1, 2001). This classification is due to their wide distribution, presumably large population and the low likelihood of rapid population decline that would warrant a higher threat category.

Mola mola

The ocean sunfish, also known as the common mola (Mola mola), is among the largest bony fish globally. It is the type species of the genus Mola and one of the five existing species in the family Molidae. Previously, it was incorrectly identified as the heaviest bony fish, a title that belongs to a closely related species, Mola alexandrini. Adult ocean sunfish generally weigh between 247 and 1,000 kg (545 and 2,205 lbs). This species is found in tropical and temperate waters worldwide.

Mole

Moles, one of the fascinating animals starting with M, are small mammals uniquely adapted to living underground. They possess cylindrical bodies, velvety fur and very small, inconspicuous eyes and ears. Their hindlimbs are reduced, while their short, powerful forelimbs are equipped with large paws designed for digging. Moles can tolerate higher levels of carbon dioxide compared to other mammals due to a special form of hemoglobin in their blood that has a greater affinity for oxygen. Additionally, they utilize oxygen more efficiently by reusing exhaled air, allowing them to survive in low-oxygen environments like burrows.

Mole Crab

The mole crab, a quirky resident of sandy beaches, isn’t your average crustacean. Unlike their lobster or crab cousins with hard shells, mole crabs have a soft, flattened body perfectly adapted for a life spent burrowing. Imagine a tiny brown shrimp with oversized claws, that’s the general idea!  They use these strong claws to dig tunnels in the sand, disappearing and reappearing with the waves. But they’re not hiding – they’re filter feeders!

Mole Cricket

Mole crickets, one of the fascinating animals that start with M, belong to the insect family Gryllotalpidae. These insects vary in size and appearance but are generally of moderate size, typically measuring between 3.2 and 3.5 cm (1.3 and 1.4 inches) in length as adults. Adapted for subterranean life, mole crickets have a cylindrical shape covered with fine, dense hairs. Their head, forelimbs and prothorax are heavily sclerotized, while the abdomen remains relatively soft. The head features two thread-like antennae and a pair of beady eyes.

Mole Snake

The mole snake (Pseudaspis cana) is a species of serpent known for its considerable size, reaching up to 2 meters (6 feet 7 inches) in total length, including the tail. This species is characterized by its small head and pointed snout, along with a firm, tubular body. The mole snake’s range covers much of southern Africa and it is particularly common in Kalahari Gemsbok National Park. Its distribution extends widely, from Angola in the north to Kenya in the east and down to South Africa.

Mollusk

The mollusk world is a vast and surprisingly diverse underwater (and sometimes aboveground) kingdom. Mollusca, with around 76,000 recognized extant species and an estimated 60,000 to 100,000 fossil species, is the second-largest animal phylum after insects. That’s right, these fascinating creatures encompass a wider variety than you might think, from the familiar snails and clams we see on the beach to the majestic octopuses and squids that glide through the ocean depths.

Molly

Molly, also known scientifically as Poecilia sphenops, is a popular freshwater fish among aquarists, renowned for its hardiness and vibrant variety. Originating from the warm waters of Central and South America, these livebearers are often praised for their ease of care and adaptability to different water conditions. Molly fish, one of the fascinating animals that start with M, come in an array of colors and patterns, from the classic black molly to the striking dalmatian molly, making them a favorite for adding visual appeal to home aquariums. Beyond their aesthetic allure, mollies play a practical role in aquariums by helping to control algae growth.

Monarch Butterfly

The monarch butterfly (Danaus plexippus), also known simply as the monarch, is a type of milkweed butterfly. Physiological studies indicate that monarch butterflies perceive their environment through a tetrachromatic vision system. Like humans, their retinas contain three types of opsin proteins, which are present in distinct photoreceptor cells, each absorbing light at different wavelengths.

The range of the western and eastern populations of D. p. plexippus fluctuates with the seasons, varying between breeding areas, migration routes and wintering sites. Despite these differences, there are no genetic distinctions between the western and eastern populations; reproductive isolation has not resulted in subspeciation within these groups, unlike other populations within the species’ range. Curious for more? Read the full article here!

Mongoose

A mongoose is a small carnivorous mammal that belongs to the family Herpestidae. This family is divided into two subfamilies: Herpestinae, with 23 species found in southern Europe, Africa and Asia and Mungotinae, with 11 species native to Africa. The Herpestidae family dates back to approximately 21.8 ± 3.6 million years ago in the Early Miocene and diverged into two primary genetic lineages between 19.1 and 18.5 ± 3.5 million years ago.

Mongooses, one of the fascinating animals that start with M, are recognized by their elongated bodies and faces, small rounded ears, short legs and long, tapering tails. Their fur is usually brindled or grizzled, though some species have distinct markings similar to those of mustelids. Mongooses have non-retractable claws that are mainly used for digging and their eyes feature narrow, oval-shaped pupils akin to those of goats.

Mongrel

A mongrel, mutt, or mixed-breed dog refers to a canine that does not belong to a specific recognized breed, including those produced through deliberate crossbreeding. While the term “mixed-breed dog” is often preferred, many mongrels have no known purebred lineage. According to the theory of hybrid vigor, dogs with diverse ancestry tend to be healthier overall compared to their purebred counterparts. In purebred dogs, breeding animals with similar appearances over multiple generations can result in a high concentration of the same alleles, some of which may be harmful.

Monitor Lizard

Monitor lizards, one of the fascinating animals that start with M, belong to the genus Varanus, which is the sole surviving genus in the family Varanidae. These lizards are indigenous to Africa, Asia and Oceania, with one species introduced to the Americas as an invasive species. There are approximately 80 recognized species within this genus.

Characterized by their long necks, powerful tails, sharp claws and well-developed limbs, monitor lizards vary significantly in size. Adult lengths range from 20 cm (7.9 in) in species like Varanus sparnus to over 3 meters (10 feet) in the Komodo dragon. The extinct Varanus priscus, also known as megalania, is believed to have grown over 7 meters (23 feet) long. While most monitor lizards are primarily terrestrial, many species exhibit arboreal or semiaquatic lifestyles.

Monkey

The term “monkey” commonly refers to most mammals within the infraorder Simiiformes, also known as simians. Traditionally, all members of the simian group are considered monkeys, with the exception of apes. However, since apes are phylogenetically related to Old World monkeys as their sister group, many characteristics defining monkeys are also applicable to apes. Williams et al. discussed evolutionary traits, including those in stem groupings, which differentiate simians from other primates like tarsiers and lemuriformes.

Monkeys exhibit a wide range in size, from the diminutive pygmy marmoset, measuring about 117 mm (4.6 inches) with a 172 mm (6.75 inches) tail and weighing just over 100 grams (3.5 ounces), to the larger male mandrill, which can reach nearly 1 meter (3 feet 3 inches) in length and weigh up to 36 kilograms (79 pounds).

Monkfish

Members of the genus Lophius, often referred to as monkfish, fishing-frogs, frog-fish and sea-devils, comprise various species of lophiid anglerfishes inhabiting the Atlantic and Indian Oceans. These monkfish are distinguished by their highly compressed heads and bodies. Their frontal ridges are adorned with low, blunt knobs or cross ridges. Additionally, they possess a prominent spine on the parietal bone and spines on the lower quadrate bone. The soft-rayed section of their dorsal fin contains between 9 and 12 rays, while their anal fin has 8 to 10 rays. The gill openings extend below and behind the base of the pectoral fin.

Monocled Cobra

The monocled cobra (Naja kaouthia), also known as the monocellate cobra or Indian spitting cobra, is a venomous snake species prevalent throughout South and Southeast Asia. It is classified as Least Concern on the IUCN Red List. This cobra is distinctive for its O-shaped, or monocellate, hood pattern, in contrast to the Indian cobra, which displays a “spectacle” pattern consisting of two connected circular ocelli on the back of its hood.

The cobra’s elongated nuchal ribs allow it to flare out the front of its neck into a “hood.” Juveniles typically exhibit more consistent coloration, while adults may display a range of colors including yellow, brown, gray, or blackish, with or without irregular or clearly defined cross bands on the dorsal surface.

Monte Iberia Eleuth

The Monte Iberia eleuth (Eleutherodactylus iberia), also known as the Monte Iberia dwarf frog, is a critically endangered species of frog from the eleutherodactylid family. Endemic to the rainforest of a small region in easternmost Cuba, this frog is notable for being the smallest in the Northern Hemisphere and the third smallest worldwide. It is generally darker in color, with the lines on its back not extending as far to the rear. Due to its extreme miniaturization, the Monte Iberia eleuth has fewer teeth compared to related species and a laryngeal apparatus that is as small as the head of a pin.

Moon Jellyfish

Moon jellyfish, scientifically known as Aurelia aurita, are fascinating creatures found in oceans around the world, often recognized by their translucent, bell-shaped bodies and delicate, pulsating movements. These ethereal beings, typically measuring between 10 to 16 inches in diameter, drift gracefully through coastal waters, propelled by the rhythmic contractions of their umbrella-like bells.

Their distinctive appearance is highlighted by four horseshoe-shaped gonads, visible through their almost transparent skin. Moon jellies primarily feed on plankton, which they capture with the aid of their marginal tentacles and transport to their mouth located on the underside of the bell.

Moonglow Boa

The Moonglow Boa, a stunning example of genetic engineering in reptiles, is a captivating morph of the Boa constrictor species. Renowned for its ethereal, almost otherworldly appearance, this snake exhibits a luminous, pearly white coloration with subtle, pale markings that give it a ghostly glow under certain lighting.

This unique appearance is achieved through the combination of three genetic traits: hypomelanism (reducing black pigmentation), anerythrism (eliminating red pigmentation) and albino genes (removing all dark pigmentation). Originating from the Boa constrictor imperator subspecies, which is native to Central America, the Moonglow Boa thrives in a captive environment when provided with the proper care.

Moorhen

Moorhens, also known as marsh hens, are medium-sized water birds belonging to the rail family (Rallidae). These birds typically exhibit brown and black plumage with some white markings. Unlike many other rail species, moorhens are often visible as they feed along open water margins rather than staying concealed in reedbeds.

With short, rounded wings, moorhens are not strong fliers but can still cover considerable distances. For instance, the common moorhen can migrate up to 2,000 km (1,200 miles) from its breeding grounds in the colder regions of Siberia.

Moose

The moose (Alces alces) holds the title as the tallest, largest and heaviest living species of deer and it is the only member of the genus Alces. Additionally, it is the tallest and second-largest land animal in North America.

An adult moose typically stands between 1.4 to 2.1 meters (4 feet 7 inches to 6 feet 11 inches) tall at the shoulder, which is more than 30 centimeters (1 foot) taller than the next-largest deer, the wapiti. The moose has a short, vestigial tail measuring 6 to 8 centimeters, which is too short to effectively swish away insects, unlike other ungulates. Male moose, or “bulls,” generally weigh between 380 to 700 kilograms (838 to 1,543 pounds), while females, or “cows,” weigh between 200 to 490 kilograms (441 to 1,080 pounds). These weights can vary based on factors such as subspecies, age and nutritional status.

Moray Eel

Moray eels, belonging to the family Muraenidae, are a diverse group of eels found globally. This family includes around 200 species across 15 genera, predominantly inhabiting marine environments. While moray eels are primarily found in saltwater, a few species can also be found in freshwater habitats. Most species, however, remain strictly marine. These eels are opportunistic carnivores, preying mainly on smaller fish, crabs and octopuses.

Morkie

The Morkie, a delightful hybrid breed, is the charming result of crossing a Maltese with a Yorkshire Terrier. Known for its small size, typically weighing between 4 to 12 pounds, the Morkie combines the best traits of both parent breeds, making it an affectionate and lively companion. Its coat, which can range from silky straight to slightly wavy, often features a mix of colors including black, brown and white, adding to its appeal. Morkies are renowned for their playful and energetic personalities, requiring regular exercise and mental stimulation to stay happy and healthy.

Morpho Butterfly

Morpho butterflies encompass numerous species of Neotropical butterflies within the genus Morpho. This genus consists of over 29 recognized species and 147 recognized subspecies, primarily found in South America, Mexico, and Central America.

Morpho butterflies, one of the fascinating animals that start with M, are renowned for their metallic, shimmering blue and green hues. They predominantly inhabit the primary forests of the Amazon and Atlantic, but have also adapted to a variety of other forested environments, such as Nicaragua’s dry deciduous woodlands and secondary forests. These butterflies can be found at altitudes ranging from sea level up to approximately 1,400 meters (4,600 feet).

Mosasaurus

Mosasaurus, known as the “lizard of the Meuse River,” is the type genus of the mosasaurs, an extinct group of aquatic squamate reptiles. It existed approximately 82 to 66 million years ago during the Campanian and Maastrichtian stages of the Late Cretaceous period. Mosasaurus was a highly evolved mosasaur, exhibiting advanced traits suited for a fully aquatic life. These traits included a streamlined body, an elongated tail with a downward turn that supported a two-lobed fin, and two pairs of flippers.

Moscow Watchdog

The Moscow watchdog, originally bred in the former Soviet Union (now Russia), is a powerful guard dog that emerged from a mix of St. Bernard, Caucasian Shepherd Dog, and Russian Pinto Hound breeds. These dogs are quite large, with males standing at least 68 centimeters (27 inches) tall and females at 66 centimeters (26 inches). However, the ideal height is a bit more substantial: males should be around 77–78 centimeters (30–31 inches) and females about 72–73 centimeters (28–29 inches). The breed’s weight is similarly impressive, with males weighing a minimum of 55 kilograms (121 pounds) and females at least 45 kilograms (99 pounds). Moscow watchdogs have a thick, double-layered coat designed to endure severe cold temperatures. Their coat can come in various colors, including red piebald, white with red spots, red-black, black-red, or sable spots, typically featuring a black mask on the head.

Mosquito

Mosquitoes, belonging to the Culicidae family, encompass around 3,600 species of small flies. Similar to other flies, mosquitoes undergo a four-stage life cycle: egg, larva, pupa, and adult. The initial three stages—egg, larva, and pupa—are predominantly aquatic, with eggs typically deposited in stagnant water. These eggs hatch into larvae, which feed, grow, and molt until they transform into pupae.

The adult mosquito then emerges from the mature pupa while it is at the water’s surface. Adult mosquitoes have a lifespan ranging from about a week to a month, with some species surviving through the winter in a state of diapause. Both male and female mosquitoes consume nectar, aphid honeydew, and plant juices. However, in numerous species, females also act as blood-sucking ectoparasites.

Moth

Moths, often overshadowed by their daytime relatives, butterflies, are fascinating and ecologically significant insects belonging to the order Lepidoptera. With over 160,000 species documented worldwide, moths exhibit incredible diversity in size, shape, and coloration.

Unlike butterflies, which are primarily diurnal, moths are mostly nocturnal and are attracted to light sources at night. Their wings are often covered in scales that create intricate patterns and colors, serving as camouflage or warning signals to predators. Moths play a crucial role in ecosystems as pollinators; many species are specially adapted to pollinate night-blooming flowers, contributing to the reproductive success of various plants.

Mountain Beaver

The mountain beaver (Aplodontia rufa) is a rodent species found in North America. These animals usually exhibit dark gray or brown fur, though variations can occur, with some having a more reddish (rufa) or blackish tint, depending on the subspecies. Notably, they possess short tails and light-colored patches under each ear. Adult mountain beavers typically weigh between 500 and 900 grams (18–32 ounces), with some exceptional specimens weighing up to 1,000 grams (35 ounces). Their overall body length spans from 30 to 50 centimeters (12–20 inches), with tail lengths ranging from 1 to 4 centimeters (0.39–1.57 inches).

Mountain Bluebird

The mountain bluebird (Sialia currucoides) is a small migratory thrush inhabiting the mountainous regions of western North America. This bird is easily identifiable by its light underbelly and dark eyes. Adult males feature slender bills and are a striking turquoise-blue, with a slightly paler underside.

In contrast, adult females have more subdued blue on their wings and tail, along with a gray breast, crown, throat, and back. Measuring between 15.5 and 18 cm (6.1–7.1 inches) in length, mountain bluebirds weigh approximately 24 to 37 grams (0.85–1.31 ounces) and boast a wingspan ranging from 28 to 36 cm (11.0–14.2 inches). While the sexes differ in plumage color, they are similar in size.

Mountain Cur

The Mountain Cur, one of the fascinating animals that start with M, is a versatile working dog bred specifically for treeing and trailing small game such as squirrels and raccoons. They excel in hunting larger game like bear and wild boar and serve as capable all-purpose farm dogs. Belonging to the Hound group, Mountain Curs are one of several cur varieties characterized by their short coats, which can be blue, black, yellow, brown, or brindle, often with white markings on the face or chest. They typically weigh between 30 and 60 pounds, with males standing 18 to 26 inches tall and females ranging from 16 to 24 inches in height.

These dogs are intelligent, easily trainable, and exhibit neither aggression nor shyness. They have a strong desire to please their owners and generally get along well with children and other pets. Due to their working background, Mountain Curs may become anxious or bored if they lack opportunities to hunt, guard, or engage in farm work.

Mountain Feist

The Treeing Feist, one of the fascinating animals that start with M, originates from the Southeastern United States and was initially considered a single breed alongside the Mountain Feist, though they are now recognized separately by the United Kennel Club. These dogs are known for their small size, agility, and keen alertness. They sport short, dense coats that come in a variety of colors and patterns. Treeing Feists typically have upright or semi-pricked ears, and their tails may be docked or left natural in any length. Originally, they varied greatly in size, ranging from 10 to 22 inches (25–56 cm) in height and 10 to 35 pounds (4.5–15.9 kg) in weight.

Mountain Gorilla

The mountain gorilla (Gorilla beringei beringei) represents one of the two subspecies of the eastern gorilla and is currently classified as endangered by the IUCN since 2018. These gorillas possess fur that is typically thicker and longer compared to other gorilla species, allowing them to thrive in colder climates. Each gorilla can be identified by unique nose prints. Adult males exhibit prominent bony crests on the top and back of their skulls, giving their heads a more conical appearance. These crests serve as attachments for powerful temporalis muscles that connect to the lower jaw. Adult females also have these crests, albeit less pronounced. Like all gorillas, they have dark brown eyes encircled by a black ring around the iris.

Mountain Lion

The cougar (Puma concolor), known by various names such as panther, mountain lion, catamount, and puma, is a large feline native to the Americas. It ranges across North, Central, and South America, making it the most widely distributed wild terrestrial mammal in the Western Hemisphere and one of the most prevalent worldwide. Cougars have a round head and erect ears, with powerful forequarters, neck, and jaws adapted for grasping and holding large prey. They possess four retractable claws on their hind paws and five on their forepaws, including a dewclaw. The larger front feet and claws are specialized for gripping prey.

As members of the Felidae family, cougars are slender and agile. They rank as the fourth largest cat species globally, with adults typically standing between 60 and 90 cm (24 to 35 inches) tall at the shoulders. Adult males can measure around 2.4 meters (7 feet 10 inches) from nose to tail tip, while females average about 2.05 meters (6 feet 9 inches), with overall lengths ranging from 1.50 to 2.75 meters (4 feet 11 inches to 9 feet 0 inches) for the species as a whole.

Mourning Dove

The mourning dove (Zenaida macroura) belongs to the dove family, Columbidae, and is also known by various names including the American mourning dove, rain dove, chueybird, colloquially as the turtle dove, and historically as the Carolina pigeon and Carolina turtledove.

This medium-sized dove measures approximately 31 cm (12 inches) in length and typically weighs between 112 and 170 g (4.0–6.0 oz), with an average closer to 128 g (4.5 oz). It boasts a wingspan ranging from 37 to 45 cm. The mourning dove is characterized by broad, elliptical wings and a rounded head. Its distinctive feature is its long, tapered tail (with “macroura” originating from Greek words meaning “large” and “tail”). Mourning doves have feet designed for perching, with three toes forward and one reversed, and their legs are short and reddish in color. The beak is short and usually dark, often appearing brown-black in hue.

Mourning Gecko

Lepidodactylus lugubris, commonly known as the mourning gecko or common smooth-scaled gecko, is a type of lizard found in various regions. These geckos typically measure between 8.5 and 10 cm in length, including their tail (4–4.4 cm from snout to vent). They are cryptically colored, often ranging from light to dark tan with dark spots along their back and a brown stripe extending from the ear to the tip of the nose. Notably, this species has the ability to change its coloration, allowing the same individual to appear light or dark at different times of the day.

Mourning Warbler

The mourning warbler (Geothlypis philadelphia) is a small songbird belonging to the New World warbler family. Native to eastern and central North America, as well as certain countries in Central America, these birds are neotropical migrants typically found in dense second-growth forests. They are categorized under Wood-warblers, a group that includes colorful passerines both arboreal and terrestrial. Both male and female mourning warblers measure between 10 and 15 cm (3.9-5.9 inches) in length and weigh between 11 and 13 g (0.4-0.5 oz). They have a wingspan of about 18 cm (7.1 inches).

Mouse

A mouse is a small rodent characterized by its pointed snout, small rounded ears, and a scaly tail that is about the same length as its body. Known for their rapid reproduction, mice are prolific breeders. The most familiar species is the common house mouse (Mus musculus), which is also popular as a pet.

Certain types of field mice are locally abundant in some regions and may invade homes in search of food and shelter. In the wild, mice primarily consume fruits and grains, displaying herbivorous tendencies. However, they adapt well to urban environments and are notorious for consuming almost any type of food scraps. When kept in captivity, mice are typically fed a balanced commercial pelleted diet designed for their nutritional needs, although they also require a diverse array of vegetables for optimal health.

Mouse Spider

The Mouse Spider (Missulena spp.) is a robust and intriguing arachnid native to Australia, known for its potent venom and unique behaviors. Despite its name, which suggests a resemblance to mice in size and appearance, these spiders are actually medium to large-sized, ranging from 1 to 3 centimeters in body length. They are typically dark-colored, ranging from brown to black, with glossy exteriors and robust, powerful legs designed for burrowing rather than web-spinning.

Mouse Spiders, one of the fascinating animals that start with M, are solitary and nocturnal predators, inhabiting burrows that can extend up to 30 centimeters underground, where they wait patiently for prey to pass by. Their venom, although primarily designed to immobilize their preferred diet of insects, is also potent enough to cause discomfort and potential medical issues in humans if bitten.

Mouse-Deer

Chevrotains, also known as mouse-deer, are tiny, even-toed ungulates that belong to the family Tragulidae. These creatures are typically solitary but can occasionally be found in loose groups or pairs. Their diet is predominantly composed of plant matter. Chevrotains hold the title of the smallest hoofed mammals globally. The Asian varieties weigh between 0.7 and 8.0 kg (1.5 to 17.75 lb), while the African chevrotain is significantly heftier, weighing between 7 and 16 kg (15 to 35 lb). The Java mouse-deer, measuring an average of 45 cm (18 in) in length and 30 cm (12 in) in height, is the tiniest living ungulate and the smallest artiodactyl (even-toed ungulate).

Mozambique Spitting Cobra

The Mozambique spitting cobra (Naja mossambica) is a highly venomous spitting cobra species indigenous to Africa. It is predominantly found in countries such as Angola, Botswana, Malawi, Mozambique, Namibia, South Africa, Tanzania, Zambia, and Zimbabwe.

The snake’s coloration ranges from slate to blue, olive, or tawny black on the upper side, with black-edged scales. Its underside is salmon pink to purplish yellow, adorned with black bars across the neck, and ventral scales that are speckled or edged with brown or black. Juvenile cobras may exhibit pink or yellow bars on their throats. Adult Mozambique spitting cobras typically measure between 90 cm and 105 cm (3 to 3½ feet) in length, with the largest recorded specimen being a 154 cm (5 feet) long male found in Durban, KwaZulu-Natal, South Africa.

Mud Snake

The mud snake (Farancia abacura), one of the fascinating animals that start with M, is a nonvenomous, semi-aquatic colubrid snake native to the southeastern United States. Typically, mud snakes reach lengths of 40 to 54 inches (1 to 1.4 meters), though the longest recorded individual measured just over 80 inches (2 meters). This species exhibits sexual dimorphism in size, with females being generally larger than males.

The upper side of the mud snake is characterized by a glossy black coloration, while the underside features a striking pattern of red and black. The red coloration extends up the sides, creating reddish-pink bars. However, some mud snakes are entirely black, displaying only slightly lighter black spots rather than the usual red hues.

Mudi

The Mudi, originating from Hungary, is a herding dog breed closely related to the Puli and Pumi, from which it was distinguished in the 1930s. Known for their high energy levels, Mudis excel in herding and agility and are also active participants in various dog sports. With appropriate care, their lifespan ranges from 12 to 14 years. Adult Mudis typically stand 14 to 18 inches tall and weigh between 18 and 29 pounds. They have a medium-length, curly coat and can be born with tails of varying lengths, from bobtails to long, full-length tails.

Mudpuppy

Necturus is a genus of aquatic salamanders belonging to the family Proteidae. These species are indigenous to the eastern regions of the United States and Canada and are often referred to as waterdogs and mudpuppies. Necturus salamanders exhibit paedomorphosis, meaning they retain larval characteristics into adulthood, including external gills, two pairs of gill slits, and the absence of eyelids.

They possess a moderately robust build with two pairs of short but well-developed limbs and a broad, laterally compressed tail. Although they have lungs, these are relatively small. Adult Necturus typically measure 20–25 cm (8–10 inches) in total length, though Necturus maculosus can grow larger, reaching up to 40 cm (16 inches).

Mudskipper

Mudskippers, one of the fascinating animals that start with M, are a unique group of 23 existing species of amphibious fish. These fascinating creatures can reach lengths of up to 30 cm (12 inches) and typically exhibit a brownish-green coloration, which can vary from dark to light shades. During the breeding season, male mudskippers develop vibrant spots in hues of red, green, or blue to attract females. Unlike typical fish, mudskippers have eyes that protrude from the top of their flat heads. However, their most distinctive feature is their side pectoral fins, which are positioned more forward and underneath their elongated bodies.

Mule

The mule is a domestic hybrid animal resulting from the crossbreeding of a male donkey (jack) and a female horse (mare). Typically, in both mules and hinnies, the front parts and head resemble those of their sire, while the hindquarters and tail reflect the dam’s characteristics. Mules are generally larger than hinnies, boasting longer ears, a heavier head, and a tail covered with long hair like that of their horse mother. They come in a wide range of sizes, from small miniature mules less than 125 cm (50 inches) tall to large, robust draught mules reaching up to 180 cm (70 inches) at the withers. The average weight of a mule ranges between 370 and 460 kg (820 to 1,000 pounds).

Mule Deer

The mule deer (Odocoileus hemionus) is a species of deer native to western North America, known for its large, mule-like ears. This species includes two subspecies collectively referred to as black-tailed deer. Key distinctions between mule deer and white-tailed deer include differences in ear size, tail coloration, and antler structure. Generally, body size also serves as a differentiating factor. The mule deer features a black-tipped tail, unlike the white-tailed deer. Additionally, the antlers of mule deer are bifurcated, meaning they split into two branches as they grow, unlike the white-tailed deer, whose antlers branch from a single main beam.

Mulga Snake

The Mulga Snake (Pseudechis australis) is a formidable reptile endemic to Australia, renowned for its imposing size, potent venom, and distinctive appearance. As one of Australia’s largest venomous snakes, adults can reach lengths exceeding 2 meters, with robust bodies adorned in glossy scales ranging from dark brown to black. These snakes inhabit arid and semi-arid regions across much of the continent, where they are adept predators known for their ambush hunting tactics.

Notwithstanding their venomous nature, Mulga Snakes are generally shy and prefer to avoid human encounters, retreating rather than attacking when threatened. Their venom, although highly potent, is used primarily to subdue prey such as small mammals and birds.

Mullet Fish

Mullets, also known as grey mullets, belong to the family Mugilidae. These ray-finned fish are found globally in coastal temperate and tropical waters, with some species also inhabiting freshwater environments. Mullets have been a vital food source in Mediterranean Europe since the era of the Roman Empire. This family comprises around 78 species spread across 26 genera. A notable behavior of mullets is their frequent leaping out of the water. They exhibit two distinct types of leaps: a swift, clean leap to evade predators and a slower, sideways jump that creates a larger and more noticeable splash.

Muntjac

Muntjacs, commonly referred to as barking deer or rib-faced deer, belong to the genus Muntiacus and are indigenous to South Asia and Southeast Asia. Male muntjacs have short antlers that can regrow, but they primarily use their “tusks”—downward-pointing canine teeth—to fight for territory. These distinctive “tusks” are unique among native British wild deer and can help identify a muntjac from an immature native deer.

Muscovy Duck

The Muscovy duck (Cairina moschata) is a species indigenous to the Americas, ranging from the Rio Grande Valley in Texas and Mexico down to Argentina and Uruguay. This large duck species sees males growing up to 76 cm (30 inches) in length and weighing as much as 7 kg (15 pounds). Females are significantly smaller, reaching only about 3 kg (6.6 pounds), approximately half the size of males. Muscovy ducks are primarily black and white, with males displaying iridescent and glossy back feathers, while females have a more subdued appearance. The amount of white on their neck and head can vary, and their bills may be yellow, pink, black, or a combination of these colors.

Musk Deer

Musk deer, one of the fascinating animals that start with M, refer to any one of the seven species within the genus Moschus. These animals resemble small deer, featuring a stocky build and longer hind legs compared to their front legs. They typically measure between 80 and 100 cm (31 to 39 inches) in length, stand 50 to 70 cm (20 to 28 inches) tall at the shoulder, and weigh between 7 and 17 kg (15 to 37 pounds). Musk deer’s feet are specially adapted for climbing rugged terrain. Unlike other deer species, such as the Chinese water deer, musk deer do not have antlers. Instead, males possess elongated upper canines that form saber-like tusks.

Muskellunge

The muskellunge (Esox masquinongy), commonly known as muskie, musky, ski, or lunge, is a large freshwater predatory fish found in North America. Similar to the northern pike and other pike species, muskellunge have a body designed for ambush predation, featuring an elongated shape, a flat head, and fins (dorsal, pelvic, and anal) positioned far back on the body. They typically measure between 70 and 120 cm (28–48 inches) in length and weigh between 7 and 16.5 kg (15–36 pounds). However, some muskies have grown as large as 1.8 meters (6 feet) and nearly 30 kg (70 pounds). In November 2000, Martin Arthur Williamson caught a remarkable muskellunge weighing 27.8 kg (61.25 pounds) in Georgian Bay.

Muskox

The muskox (Ovibos moschatus) is a hoofed mammal known for its long, curved horns present in both males and females. These animals stand between 1.1 and 1.5 meters (3 feet 7 inches to 4 feet 11 inches) tall at the withers. Females range from 135 to 200 cm (4 feet 5 inches to 6 feet 7 inches) in length, while the larger males measure 200 to 250 cm (6 feet 7 inches to 8 feet 2 inches). They have a small tail, usually hidden beneath their fur, that is about 10 cm (3.9 inches) long. In the summer, muskoxen inhabit wet areas like river valleys and migrate to higher elevations during winter to escape deep snow. Their diet consists of grasses, arctic willows, woody plants, lichens, and mosses.

Muskrat

The muskrat (Ondatra zibethicus) is a medium-sized, semiaquatic rodent native to North America and has been introduced to regions in Europe, Asia, and South America. It thrives in wetlands across a variety of climates and habitats, playing a vital role in wetland ecosystems and serving as a source of food and fur for humans.

Adult muskrats typically weigh between 0.6 and 2 kg (1.25 to 4.5 pounds) and have a body length of 20 to 35 cm (8 to 14 inches), excluding the tail. They are covered in short, thick fur that ranges from medium to dark brown. Their long, scaly tails are laterally compressed and aid in generating thrust, while their webbed hind feet serve as the primary means of propulsion. The distinctive tail is particularly important for maintaining directional stability in the water.

Mussurana Snake

The Mussurana Snake, scientifically known as Clelia clelia, is a fascinating serpent found primarily in Central and South America, known for its unique diet and behavior. Unlike typical snakes, the Mussurana has evolved to prey exclusively on other snakes, particularly venomous species such as pit vipers and coral snakes. This specialization is facilitated by adaptations in their anatomy and behavior, including immunity to venom and a powerful constricting ability that allows them to overpower and consume their prey safely.

Their slender bodies, reaching lengths of up to 2 meters, are typically grayish-brown with darker markings, aiding in camouflage among the forest floor and dense vegetation where they dwell.

Muttaburrasaurus

Muttaburrasaurus was a genus of herbivorous iguanodontian ornithopod dinosaur that roamed northeastern Australia between 112 and 103 million years ago during the early Cretaceous period. Measuring approximately 8 meters (26 feet) in length and weighing around 2.8 metric tons (3.1 short tons), this dinosaur is notable for its significant size. The femur of the holotype specimen is 1,015 millimeters (40 inches) long.

There has been ongoing debate regarding the Muttaburrasaurus’s ability to move on all fours. Initially classified as an “iguanodontid,” recent studies suggest it belongs to the rhabdodont group. Ornithopods at such a basal evolutionary stage were generally incapable of quadrupedal locomotion.

Myna Bird

Mynas are a group of birds belonging to the starling family (Sturnidae). These passerine birds are native to Southern Asia, particularly in countries like Afghanistan, India, Pakistan, Bangladesh, Nepal, and Sri Lanka. Mynas are medium-sized with robust feet, and they exhibit strong, direct flight patterns. Known for their sociable nature, they thrive in relatively open habitats and primarily feed on insects and fruit. Their plumage is generally dark, often brown, with some species featuring yellow head ornaments. Most mynas prefer to nest in cavities.

As we reach the end of our journey through the fascinating list of animals that start with M, we hope you’ve discovered new and intriguing facts about these magnificent creatures. From the majestic moose to the mischievous marmoset, each animal has its own unique story and characteristics that enrich our planet’s biodiversity.