Animals That Start With M

This page includes all animals that start with the letter M that we plan to cover on Fact Animal. As we publish new content, each of these animals will be linked to their dedicated profile fact pages.

From the Macaw to Muskox, read extraordinary facts about animals beginning with the letter M.

M

Macaque
Macaroni Penguin
MacGillivray’s Warbler
Mackenzie Valley Wolf
Macrauchenia
Macaw
Madagascar Hissing Cockroach
Madagascar Jacana
Madagascar Tree Boa
Madora
Magellanic Penguin
Magnificent Frigatebird
Maggot
Magnolia Warbler
Magpie
Mahi Mahi (Dolphin Fish)
Maine Coon
Mal Shi
Malayan Civet
Malayan Krait
Malayan Tiger
Malchi
Mallard
Maltese
Maltese Cat
Maltese Dog
Maltese Goat
Mamba
Mamushi Snake
Man of War Jellyfish
Manatee
Manchester Terrier
Mandarin Rat Snake
Mandrill
Mangrove Snake
Mangrove Snapper
Maned Wolf
Manta Ray
Mantis Shrimp
Manx Cat
Manx Cat
Manx Shearwater
Manx Sherwater
Marabou Stork
Marans Chicken
Marble Fox
Maremma Sheepdog
Margay
Marine Iguana
Marine Toad
Maricopa Harvester Ant
Markhor
Marmoset
Marmot
Marsh Frog
Martial Eagle
Masiakasaurus
Masked Palm Civet
Masked Angelfish
Mason Bee
Massasauga
Mastador
Mastiff
Mastiff Mix
Mata Mata
Mauzer
May Beetle
Mayan Cichlid
Mayfly
Mealworm Beetle
Mealybug
Meerkat
Megalania
Megalochelys
Megalodon
Meganeura
Megatherium
Megamouth Shark
Meiolania
Mekong Giant Catfish
Merganser
Mexican Alligator Lizard
Mexican Black Kingsnake
Mexican Eagle (Northern crested caracara)
Mexican Fireleg Tarantula
Mexican Free-Tailed Bat
Mexican Mole Lizard
Midget Faded Rattlesnake
Miki
Milk Snake
Milkfish
Milkweed aphids
Millipede
Mini Lop
Mink
Minke Whale
Mississippi Kite
Moccasin Snake
Mockingbird
Mojarra
Mojave Ball Python
Mojave Rattlesnake
Mola mola (Ocean Sunfish)
Mole
Mole Crab (Sand Flea)
Mole Cricket
Mole Snake
Mollusk
Molly
Monarch Butterfly
Mongrel
Monkfish
Mongoose
Monitor Lizard
Monkey
Monkeyface Prickleback
Monocled Cobra
Monte Iberia Eleuth
Moose
Moon Jellyfish
Moonglow Boa
Moorhen
Moray Eel
Morpho Butterfly
Moscow Watchdog
Mosquito
Moth
Mountain Beaver
Mountain Bluebird
Mountain Cur
Mountain Feist
Mountain Gorilla
Mountain Lion
Mourning Dove
Mourning Gecko
Mourning Warbler
Mouse
Mouse Spider
Mouse-Deer (Chevrotain)
Mozambique Spitting Cobra
Mudskipper
Mud Dauber
Mud Snake
Mudi
Mudpuppy
Mule
Mule Deer
Mulga Snake
Mullet Fish
Muntjac
Muscovy Duck
Muskox
Musk Deer
Muskellunge (Muskie)
Muskrat
Mussurana Snake
Myna Bird
Myrmecophagidae

Please see our Animal A-Z list for animals that start with different letters.


Animal Names That Start With M

Read on for an overview of each of the animals listed above that begin with the letter M.

Macaque

Macaques are a genus of 23 species of funny-faced little Old World Monkeys, mostly found in Asia, but also from North Africa and Gibraltar. These are very adaptable monkeys from a range of habitats.

Macaque

Fun Fact: Macaques are the most widespread non-human primate genus, and are diverse in their range, weighing from 5kg to 18kg depending on the species.

Macaroni Penguin

Macaroni penguins are a species of crested penguin known for a distinctive yellow crest on their heads. They weigh up to 6kg and are probably the most widespread penguin species, with tens of millions of individuals all over the Subantarctic and Arctic regions.

Macaroni Penguin

Fun Fact: Despite their name, these penguins do not eat pasta; they just have a crest on their heads that looks a bit like a piece of macaroni.

Macaw

Macaws are brightly coloured parrots native to Central and South America. They are typically very large and have huge beaks and impressive vocal abilities.

Macaw

Fun Fact: Macaws have feet much like a woodpecker’s – with two toes pointing backwards. This helps them manipulate food items and hold onto cliff faces where they visit mineral deposits.

MacGillivray’s Warbler

MacGillivray’s warblers are small migratory songbirds found in North America. They grow up to about 15cm long, have olive-green and yellow plumage and spend a lot of time on the ground.

Fun Fact: These small warblers are surprisingly sluggish and stocky, and spend more time on the ground than most species. They typically forage below 3 meters.

Mackenzie Valley Wolf

Mackenzie Valley wolves, also known as Canadian timber wolves, are a huge subspecies of grey wolf native to North America. They can weigh over 60kg.

Fun Fact: These wolves are possibly the largest grey wolf subspecies found anywhere in the world. This is the subspecies that was famously and successfully reintroduced into Yellowstone.

Macrauchenia

Macrauchenia is an extinct genus of large, camel-like herbivorous mammal from South America. They weighed up to a tonne and may have had a long, prehensile lip.

Fun Fact: This strange herbivore was from an extinct order of mammals that mostly went extinct when South America joined North America. This genus likely was finished off by human hunters.

Madagascar Hissing Cockroach

Madagascar hissing cockroaches are unsettlingly large, 8 cm-long cockroaches endemic to the island of Madagascar, named for their loud hissing they scare you with when you pick them up.

Fun Fact: Like geese, these cockroaches are all talk, no trousers. They are entirely harmless and can be easily picked up and eaten.

Madagascar Jacana

Madagascar jacanas are pretty wading birds with ridiculously long toes that enable them to walk on floating vegetation in wetland habitats. As the name suggests, they’re endemic to Madagascar.

Fun Fact: Male Madagascar jacanas are responsible for building nests and caring for the eggs and chicks, while females go off and mate with multiple partners.

Madagascan Tree Boa

Madagascan tree boas are non-venomous arboreal constrictors found in Madagascar. They have cryptic woodland colouration and grow to over 2 meters long.

Fun Fact: There are no python species in Madagascar, so this boa fills a niche that is typically filled by pythons in mainland Africa.

Madora

Madora moths are beautiful moths from Southern Africa. They’re also called mopane moths for their preference for feeding on mopane trees. They have large, brown wings with distinctive eyespots.

Fun Fact: This moth species is an important source of animal protein for many local human populations in their range.

Magellanic Penguin

Magellanic penguins are medium-sized penguins from the coasts of South America. They grow up to around 6kg and are medium-sized, stocky birds.

Fun Fact: Despite foraging off the coast of South America, they share a remarkably similar diet to their Antarctic cousins, benefitting from ocean currents that bring Antarctic fishes to the continent.

Maggot

Maggots are the wriggly, leathery larval stage of various fly species, commonly found in decaying organic matter such as rotting food or animal carcasses.

Fun Fact: While some maggots will happily burrow into your skin and swell up at your expense, other species are still used to help with wound cleaning in medical settings.

Magnolia Warbler

Magnolia warblers are small, New World songbirds with striking yellow and black plumage. They grow to about 13cm tall.

Fun Fact: These tiny birds migrate all the way from Central Canada to Central America each year, with males heading out 2 weeks before females to get everything ready.

Magpie

Magpies are super intelligent and social corvids recognised by their striking black and white plumage. This isn’t a monophyletic group and members of four different genera are often called magpies.

Fun Fact: The Eurasian magpie is one of the world’s most intelligent animals, able to recognise itself in a mirror, speak English and use tools.

Mahi Mahi (Dolphin Fish)

Mahi Mahi, also known as dolphin fish or dorado, are large and pretty marine fish found in tropical and subtropical waters worldwide. They are long, and get wider from the tail to the head, stopping suddenly at a very flat face.

Fun Fact: Mahi Mahi means “very strong”, and these fish are said to put up a good fight with fishermen.

Maine Coon

Maine Coon cats are large domesticated cats with long fur, originally from the state of Maine in the United States. They’re known for their friendly and sociable nature, often being compared to dogs.

Fun Fact: Maine Coons are one of the oldest natural breeds in the US and were named after a myth that they are a hybrid between a cat and a raccoon.

Malshi

Malshi dogs are a crossbreed between Maltese and Shih Tzu breeds. They’re very small, easy to care for, and have hypoallergenic coats.

Fun Fact: Malshi dogs are often referred to as “designer dogs” and are popular as companion animals. While the breeds they descend from are ancient, the malshi itself is a very recent cross.

Malayan Civet

Malayan civets are nocturnal and elusive viverrids from Southeast Asia, known for their nocturnal habits and ability to climb trees.

Fun Fact: These civets are key to the production of kopi luwak, a type of coffee made from coffee beans that have been eaten and excreted by the civets.

Malayan Krait

Malayan, or blue kraits are highly venomous elapid snakes found in Southeast Asia. They’re very vividly coloured with contrasting black and white bands and grow to about a metre long.

Fun Fact: Despite their highly dangerous venom, these snakes are shy and usually avoid confrontations with humans unless provoked.

Malayan Tiger

Malayan tigers are a critically endangered population of tigers endemic to the Malay Peninsula. They’re smaller than Bengal tigers but look almost identical otherwise.

Fun Fact: 200 years ago, Singapore was a thick jungle island, and this tiger was common there until an attack on a person led to widespread tiger hunting.

Mallard

Mallards are common dabbling ducks found in various regions worldwide. They’re possibly the most well-known phenotype, with males sporting iridescent green or blue heads.

Fun Fact: Male mallards have a unique, high-pitched call known as a “quack,” while females produce quieter sounds known as “decrescendo calls.”

Maltese cat

The Maltese cat is any domestic cat with grey fur. It’s not a specific breed, it just refers to a grey cat. Strangely, in the circles of cat fanatics, grey fur is called “blue”. But it’s a well-established fact that cat people are riddled with Toxoplasmosis, so they can’t help it.

Fun Fact: The Maltese cat gets its name from a population of cats said to once inhabit the island of Malta. Apparently, they were grey too.

Maltese dog

Maltese dogs are small and very silly companion breeds with long, silky white fur and often an embarrassing bow in the hair on their heads. They typically don’t weigh more than 4kg.

Fun Fact: Maltese dogs don’t shed their fur, meaning they need to be painstakingly maintained in grooming parlours to look like ancient Japanese iaido masters.

Maltese goat

The Maltese goat originates from the Mediterranean and is commonly found in Southern Italy. It has long, white hair with a contrastingly black head.

Fun Fact: This goat’s milk is said to be a lot less “goaty” than other goat milk, defeating the purpose of drinking it.

Mamba

Mambas are four species of highly venomous snakes from all over Africa, infamous for their speed, agility, and deadly potent neurotoxic venom. It is said that Marconi can play them safely, but you shouldn’t.  

Fun Fact: Mambas are Africa’s longest snakes and are among the longest and fastest snakes in the world. They can slither at speeds of up to 19 km/h and grow up to 4.3 meters long.

Mamushi Snake

Mamushi snakes are also known as Japanese pit vipers, which is exactly what they are. They have classic pit viper colouration and are one of the most venomous snakes in Japan.

Fun Fact: Mamushi venom contains hemotoxins that can cause tissue damage and internal bleeding in humans if bitten.

Man o’ War

Man o’ war “jellyfish” are marine cnidarians found in warm ocean waters, known for their distinctive blue float and long, venomous tentacles. They’re named after a 16th-century Portuguese warship.

Fun Fact: These awesome creatures are a colonial organism; a group of individual zooids, clones from a single egg, separated into various roles as “body parts” of the total organism.

Manatee

Manatees are large aquatic mammals found in warm waters. They’re sort of like slow-floating cow torpedoes and are said to be very gentle in nature. They eat grass and generally mind their own business.

Fun Fact: Manatees are closely related to elephants and hyraxes on land and are closest to dugongs in the water, but have a paddle, rather than a C-shaped tail fin.

Manchester Terrier

Manchester terriers are small, smooth-haired, sleek dogs. They are well known for their agility, intelligence, and rat-catching abilities, which made them popular in rat-baiting blood sports.

Fun Fact: These great-looking dogs have fallen out of fashion and in 1945 there were only 11 left registered in the UK.

Mandarin Rat Snake

Mandarin rat snakes are colourful and non-venomous snakes native to East Asia. Their brown skin is patterned with black and yellow markings all down the animal and they grow to about a metre long.

Fun Fact: This snake is all about rodents. It eats them, then it lives in the burrows that have just been vacated.

Mandrill

Mandrills are large and colourful baboon-like primates found in African rainforests. They have big, mean, purple and red faces in males known for their striking facial markings and social behaviours.

Fun Fact: Mandrills are the largest of the non-ape monkey species. They were once thought to be a type of hyena, then a baboon, but they’re now classed as a type of mangabey.

Mangabey

Mangabeys are three genera of rare, West African monkeys with notably lighter upper eyelids. They’re large monkeys, with tails that are longer than their bodies.

Fun Fact: Mangabeys have a special throat sac for communicating using loud noises over long distances.

Maned Wolf

Maned wolves are canids native to South America. They have long legs, reddish fur, and distinct black mane along their backs.

Fun Fact: Despite their name, and while they look like foxes, maned wolves are more closely related to bush dogs.

Mangrove Snake

There are three groups of snakes commonly called Mangrove snakes: The mildly venomous and yellow-striped Boiga dendrophila, from Asia; the small semi-aquatic Erythrolamprus cobella from South America, and the genus Myron from Australia, Indonesia and Papua New Guinea.

Fun Fact: B. dendrophila is the best-known, and is a mildly-venomous colubrid. It’s said to be quite aggressive and grows up to almost 3 meters long.

Mangrove Snapper

Mangrove snappers are Western Atlantic Snapper species. They’re usually greyish but can change colour to bright or copper red. They’re rarely more than 40cm long.

Fun Fact: As the name suggests, these fish love to spend time around mangroves, but any shelter will do. They’re commonly found around docks, reefs and wrecks.

Manta Ray

Manta rays are large, intelligent giants found in tropical marine habitats. They’re some of the largest animals in the ocean at up to 7m across and fly gracefully through the water eating plankton.

Fun Fact: Manta rays have the largest brain-to-body ratios of any fish and are commonly described as curious and playful.

Mantis Shrimp

Mantis shrimps are colourful crustaceans found in tropical waters. They’re named for their powerful claw strikes and are known for having highly complex eyesight.

Fun Fact: Mantis shrimps have some of the most sophisticated eyes in the animal kingdom, capable of detecting polarized light and a wider range of colours than most animals, though their spatial resolution is low.

Manx Cat

The Manx cat is a domestic breed from the Isle of Man. They’re mostly tailless or have a small stub for a tail but otherwise look like normal domestic cats.

Fun Fact: Folklore states that the Manx is a cross between a cat and a rabbit, or a “cabbit”. This would be impossible.

Manx Shearwater

The Manx shearwater is a seabird species known for its long migrations. They breed in Northern Europe and overwinter as far south as South Africa. They’re gull-like, with dark backs and wings and a white belly.

Fun Fact: These birds are the original puffins, with the name referring to the cured carcasses of this bird and being donated to the Atlantic puffins much later.

Marabou Stork

Marabou storks are enormous storks from sub-Saharan Africa. They have a sort of ‘ugly-cute- thing going with bald heads, testicle-like throat pouches but super sweet little eyelashes.

Fun Fact: These birds have the largest wingspan of any flying animal, tied with the American Condor.

Marans Chicken

Marans chickens are a large, domesticated chicken breed from France. They come in many different colours and lay around 200 dark brown eggs each year.

Fun Fact: The deep brown colour of Marans eggs is due to the presence of pigment molecules called porphyrins in the shell. It doesn’t affect the taste, it just looks really cool.

Marble Fox

Marble foxes are a colour morph of the red fox, characterized by their striking black and white fur pattern resembling marble. They’re bred to look awesome but make terrible pets.

Fun Fact: Marble foxes are not a wild colour morph but a product of domestication for the fur trade. They’re stunning, but as a red fox, they are highly strung and hard to take care of.

Maremma Sheepdog

Maremma sheepdogs are large, white guardian dogs from Central from Italy, originally bred to protect sheep from wolves.

Fun Fact: These little-known dogs’ presence in human culture goes well back into antiquity, with engravings and references dating back to the 1400s.

Margay

The margay is an incredible spotted cat from Central and South America. They look like ocelots but are a bit bigger, and show even more incredible agility in climbing trees.

Fun Fact: Margay females only have two teats, which, while many would say is enough, is very unusual – possibly unique – in cats.

Marine Iguana

Marine iguanas are unique reptiles found only in the Galápagos Islands. They are the only marine reptiles of the modern day and feed on marine algae that grows on rocks beneath the surface.

Fun Fact: Darwin described these incredible lizards as disgusting and clumsy. This, along with his theory of inheritance, were his two biggest mistakes.

Marine Toad

Marine toads, also known as cane toads, are large amphibians native to Central and South America. They grow to about 25cm long and are one of the largest true toads in the world.

Fun Fact: These toads secrete a powerful bufotoxin from their glands and were introduced to other countries to protect sugar cane fields but have ended up poisoning a lot of local fauna in Australia.

Markhor

Markhors are goats from Asia and the Middle East that look like they came out of a fantasy novel. The males have incredible spiralled horns and long, shaggy, grey coats.

Fun Fact: Markhor goats might be the ancestral species for a number of modern domestic goat breeds.

Marmoset

Marmosets are small New World monkeys from four genera in South America. Most are no more than 20cm long and eat insects, fruit, leaves and tree sap,

Fun Fact: Marmosets have claws instead of fingernails like most primates. They’re considered to have several so-called “primitive” features.

Marmot

Marmots are 15 species of large ground squirrels found in mountainous regions of North America, Eurasia, and Africa. They’re burrowing rodents with loud warning calls.

Fun Fact: Marmots are true squirrels, in the Sciuridae family, and they’re the largest of them all!

Marsh Frog

Marsh frogs are large water frogs from Europe and Asia. They range from brown to green and are usually 10cm long.

Fun Fact: This species has been known to hitch a ride on a water buffalo, where they get to feed on the insects that are drawn to it.

Martial Eagle

Martial eagles are huge and powerful birds of prey found in sub-Saharan Africa. They have dark wings and back with a white chest and a striking crest on the head.

Fun Fact: Martial eagles have a wingspan of up to 2.3 meters and are capable of taking down prey as large as small antelopes.

Masked Angelfish

Masked angelfish are colourful marine fish from the Hawaiian islands. It’s named for its distinctive black mask but is also brilliant white with elegant, light-blue fins.

Fun Fact: Masked angelfish are protogynous hermaphrodites, starting as females and transitioning to males as they grow larger and mature.

Mason Bee

Mason bees are solitary megachilid bees found in various warm and temperate regions worldwide. They’re named for building nests out of mud and other similar materials.

Fun Fact: Female mason bees are excellent pollinators for fruit trees and flowers, especially plants in the rose family.

Massasauga

Massasaugas are venomous pit vipers found in eastern North America. They’re often darker than most other pit vipers and small at up to 70cm long.

Fun Fact: While their venom is very dangerous to humans, these are shy snakes and will avoid confrontation where possible.

Mastador

Mastadors are large, hybrid dogs resulting from the crossing of Mastiffs and Labrador Retrievers. They have the guardian nature of the mastiff with the sort of floppy softness of a lab.  

Fun Fact: This is a very recent new breed and has only just begun to be produced by responsible breeders who know what they’re doing.

Mastiff

Mastiffs are some of the largest domestic dogs around. They have a short coat, and huge, boxy heads and have been used as hunting, fighting and war dogs for thousands of years.

Fun Fact: Mastiffs are said to descend from the ancient Greek Molossian hound, bred 5000 years ago for power and ferocity.

Mata Mata

Mata Matas are unique and ugly freshwater turtles found in South America. They look like a leaf under a rock and have long, pointed noses and long necks.

Fun Fact: This appearance serves the turtle incredibly well as an ambush predator, hiding in plain sight before lunging rapidly at its prey with a powerful bite.

May Beetle

May beetles, also known as June bugs, are two separate genera of beetles belonging to the Scarabaeidae family. One from North America, one from Europe. They’re named for coming out in May. Or June, sometimes.

Fun Fact: The European May bug is also called the cockchafer beetle, which is often said unironically and without a hint of discomfort.

Mayan Cichlid

Mayan cichlids are freshwater fish native to Central America. They grow up to 40cm and are yellow-brown with darker stripes.

Fun Fact: These fish change colour during mating season, taking on an intense red colour and becoming more aggressive and territorial.

Mayfly

Mayflies are aquatic insects found near freshwater habitats. They resemble dragonflies but are typically more delicate and hold their wings neatly above their back when landed.

Fun Fact: There are thousands of species of mayfly worldwide and they act as significant predators both as adults and in the aquatic nymphal stage.

Mealworms

Mealworms are the larvae of the mealworm beetle, a darkling beetle from the Mediterranean. They’re usually around 1.5cm to 3cm long, golden brown to grey, and have a strong exoskeleton.

Fun Fact: Mealworms are highly nutritious, easy to farm and produce very little in the way of waste or emissions. They’re authorized for human consumption in many countries.

Mealworm Beetle

Mealworm beetles are dark-colored beetles often found in grain products. They black, and have distinctive, evenly-divided linear grooves down their sides and grow to about 1.5cm long.

Fun Fact: Mealworm beetles are quickly becoming economically significant as a novelty food source and may increase in significance if they ever become a commodity.

Mealybug

Mealybugs are small, soft-bodied true bugs in the scale bug group, found in warm habitats. They feed on plant sap, and are known for their white waxy coating and habit of infesting houseplants and gardens.

Fun Fact: Only males have wings, females retain nymph-like characteristics but are significantly bigger.

Meerkat

Meerkats are small mongooses found in southern Africa. They’re known for their complex social behavior, the way they stand upright to scan for predators, and digging elaborate burrow systems.

Fun Fact: Meerkats live are highly significant engineers of their ecosystems, fertilizing an providing drainage for the very soils that the rest of the community needs to survive.

Megachilid

Megachilid bees are a family of mostly solitary bees from all over the world. They can usually be identified by the hairs on the front side of their abdomen, used for collecting pollen in females.

Fun Fact: Some species of Megachilid are parasites of other bees, so don’t have the pollen-collecting hairs on their bellies. They’ll enter the nest of another species, lay their eggs and get out before the owner comes back to close it up.

Megalania

Megalania is an extinct giant monitor lizard that lived in Australia during the Pleistocene epoch. These true monsters could have been 7m long and weighed up to two tonnes.

Fun Fact: This lizard shared Australia with early human settlers, who may have been responsible for wiping it out.

Megalochelys

Megalochelys is an extinct genus of giant tortoises from India and Pakistan. Its shell alone surpassed two meters in length and it would have weighed up to 2,000kg.

Fun Fact: These giant tortoises likely went extinct due to humans, but not our species! It’s thought this time it was Homo erectus’ fault. Phew!

Megalodon

Megalodon is an extinct species of colossal shark that lived until around 3 million years ago. This gargantuan fish may have been the largest shark to have ever lived and likely fed on equally incredible marine mammals of the time.

Fun Fact: It’s a matter of constant debate just how large this shark got to, but there’s no questioning the size of its teeth. The megalodon tooth can be up to 20 cm long and broad, like those of the great white.

Megamouth Shark

Megamouth sharks are mysterious deep-sea sharks of about five meters long. They’re brownish black and have enormous mouths, hence the name.

Fun Fact: These distinctive sharks swim with their mouths wide open, filter-feeding like the basking sharks and whale sharks. Not much else is known about it.

Meganeura

Meganeura is an extinct genus of giant dragonfly-like insects that lived during the Carboniferous period. They looked just like dragonflies except they were terrifyingly large.  

Fun Fact: Meganeura had a wingspan of 75 centimeters or more, making them some of the largest flying insects in Earth’s history. They likely could have taken a man’s hand clean off.

Megatherium

Megatherium is an extinct genus of giant ground sloths that lived in South America during the Pleistocene epoch. There were many species, and the largest would stand 3.5 meters tall and had a sharp thumb spike.

Fun Fact: These enormous mammals were genuine sloths, in the same way that ground squirrels are true squirrels. They were just 10 times the size of the sloths that remain.

Mekong Giant Catfish

Mekong giant catfish are massive freshwater fish native to Southeast Asia. They grow up to 3 meters long and can weigh 200kg.

Fun Fact: Unlike other catfish, this one has no barbels and even no teeth! Thse features appear briefly in juveniles but then disappear completely by adulthood.

Merganser

Mergansers are fish-eating diving ducks found in various regions, mostly in the Northern Hemisphere., They have slender bodies, long serrated bills, and many species sport a stylish crest on the backs of their heads.

Fun Fact: These are primarily sea ducks, but will occupy riverine systems too.

Mexican Alligator Lizard

Mexican alligator lizards are beautiful, blue or green, arboreal reptiles from Mexico. They often look like mythical creatures with colours you don’t expect in nature. They grow up to about 10cm long.

Fun Fact: These lizards spend most of their time in the branches of plants, but they can also swim really well, using the serpentine technique like monitor lizards.

Mexican Black Kingsnake

Mexican black kingsnakes are non-venomous constrictor snakes found in the deserts of Mexico and parts the southwestern United States. They’re glossy black or brown snakes of about a metre long, with a docile temperament.

Fun Fact: These snakes often feed on other species of snake and have a tolerance to various venoms that would kill other animals.

Mexican Eagle (Northern Crested Caracara)

The Mexican eagle, or crested caracara, is a raptor from Mexico and parts of the southwestern United States. They’re from the falcon family, and have long legs and orange faces with a dark head and wings.

Fun Fact: This falcon is unusual in that it gets most of its food from scavenging on carcasses. They’ve also been seen eating fruit.

Mexican Fireleg

Mexican fireleg tarantulas are fluffy and colorful spiders native to Mexico. They’re mostly black aside from bright orange legs and an orange carapace.  

Fun Fact: These are close relatives of the redknee tarantula and are long-lived at up to 8 years.

Mexican Free-Tailed Bat

Mexican (of Brazilian) free-tailed bats are medium-sized bats found in the Americas.  They’re pretty standard-looking bats, 9cm long and about 20g.

Fun Fact: These bats are the highest-flying bats of any species, attaining altitudes of over 3,300 meters.

Mexican Mole Lizard

Mexican mole lizards, also known as five-toed worm lizards, are worm-like, corrugated little reptiles native to Mexico. They’re pink or white, about 20cm long, and have tiny beady eyes.

Fun Fact: These lizards look so weird because they spend most of their time underground. Or perhaps it’s the other way around.

Midget Faded Rattlesnake

The midget faded rattlesnake is a small venomous pit viper from the southwestern United States. They have the standard rattlesnake patterns, only with far less contrast in adults. They grow to about 50cm long.

Fun Fact: Despite its small size, this snake has the most potent venom in the genus. Still, they’re not at all aggressive.

Mi-ki

Mi-kis are a small breed of dog originating from Japan in the ‘80s. They’re a mix of several breeds including the shi-tzu and Yorkshire terrier. They’re said to be very friendly and sociable.

Fun Fact: This breed is sometimes compared with a cat, not only because it’s the same size as one, but also on account of its independence and low maintenance.

Milk Snake

Milk snakes are non-venomous constrictors from the Americas. They’re brightly colorful  with banding patterns resembling those of highly venomous coral snakes.

Fun Fact: Milk snakes are named for a folk belief that they suck milk from cows, but they actually feed on small rodents, birds, and eggs, they’re just fond of living in barns.

Milkfish

Milkfish, also known as bangus, are a species of silvery fish found in tropical offshore waters of the Indian and Pacific Oceans. They’re around 1.5m long, with long, symmetrical caudal fins.

Fun Fact: These fish migrate into brackish and even fresh water to spawn, sometimes entering lakes during the spawning season.

Milkweed Bugs

Milkweed aphids are sap-sucking hemipterans from the Americas with brightly coloured red and black wings and bodies. They grow up to around 12mm long.

Fun Fact: Northernmost populations are highly migratory, travelling long distances to warmer wintering locations, while tropical populations are already quite comfortable and will stay put.

Millipede

Millipedes are ancient arthropods with elongated bodies and numerous legs, known for their defensive ability to curl into a tight spiral when threatened. They come in various sizes from a few millimeters to 3cm long.

Fun Fact: Despite their name suggesting “A thousand legs,” millipedes typically have between 30 and 400 legs, depending on the species. Each segment contains two.

Mini Lop

Mini Lops are a compact breed of domestic rabbits from Germany, known for their floppy ears, round faces, and friendly demeanor.

Fun Fact: Mini Lops apparently differ from the UK breed called miniature lop, as well as the dwarf lop and rabbit enthusiasts will take you out with a swift kick if you confuse them.

Mink

Minks are semi-aquatic mustelids native to North America and Europe. They are ferotious and sleek predators and also irresistibly cute.  

Fun Fact: Minks are skilled and generalist hunters, preying on fish, frogs, small mammals, and birds near waterways. They can bring down animals five times their weight.

Minke Whale

Minke whales are relatively tiny baleen whales at 8 tonnes and nine meters long. They’re found in the North Atlantic, North Pacific and Antarctic oceans and feed on small fish and krill.

Fun Fact: Minkies are the second-smallest baleen whale; only the pygmy right whale is smaller.

Mississippi Kite

Mississippi kites are medium-sized raptors from the Americas. They’re falcon-like, uniformly grey on the front and dark grey on the back.  found in North and South America, known for their graceful flight, aerial acrobatics, and insect-catching skills.

Fun Fact: These are very graceful in flight and commonly catch insects like cicadas on the wing.

Moccasins

Moccasin snakes, also known as cottonmouths or water moccasins, are venomous pit vipers found in southeastern United States. They are typically darker than other pit vipers and are one of the most aquatic vipers.  

Fun Fact: Moccasin snakes are named cottonmouths for their defensive display of opening their mouths wide to show their white, cotton-like interior.

Mockingbird

Mockingbirds are 17 species of songbirds found in North and South America, named for their remarkable ability to mimic the songs of other birds and sounds in their environment.

Fun Fact: Mockingbirds can imitate a wide range of sounds, including other bird species, car alarms, and even human whistles. The North American species, M. polyglottos means “many -tongued”.

Mojarra

Mojarras are a family of fish, mostly from salt and brackish waters in most tropical regions. They generally have a deeply forked tail and grow to 35cm.

Fun Fact: These fish spend their juvenile period in the murky estuarine waters where it’s safer from predators, only coming out to sea as adults.

Mojave Rattlesnake

Mojave rattlesnakes, or “Mojave greens”, are venomous pit vipers found in the southwestern United States and northern Mexico. They grow to a metre long and are commonly confused with Diamondbacks, with which they are very similar.

Fun Fact: Some populations of this species have an additional neurotoxin in their venom called “Mojave toxin”, which appears to make the venom even more deadly.

Mola Mola (Ocean Sunfish)

Mola mola, also known as ocean sunfish, are enormous and oddly-shaped fish found in oceans worldwide. They have flattened bodies, weird expressions, and an altogether unique appearance.

Fun Fact: Mola mola are the heaviest bony fish in the world, with some individuals weighing over 2000kg. They also increase in size as they age, more than any other animal: growing to 60 million times their birth size.

Mole

Moles are small, burrowing mammals in the hedgehog order. They have velvety fur and strong, shovel-like forelimbs adapted for digging. They’re typically no longer than 20cm and look cylindrical.

Fun Fact: Many mole species are surprisingly good swimmers, able to use their shovels as paddles to cross water and keep digging.

Mole Crab

Mole crabs, also known as sand crabs, are small crustaceans found on sandy beaches everywhere outside of polar regions. They’re named for their ability to quickly burrow into the sand to escape predators.

Fun Fact: Mole crabs are so adapted to digging that they can’t walk. They can swim though, by beating their tails.

Mole Cricket

Mole crickets are incredibly loud burrowing insects found in grasslands. They’re long and armoured, with powerful front limbs for digging and can be recognized for their volumous calls.  

Fun Fact: These are not true crickets, but they make up for it by digging horn-shaped burrows and sreaming their heads off at 92 decibels.

Mole Snake

Mole snakes are non-venomous constrictors from southern Africa.  They eat rodents and live much of their lives underground. They grow up to around 2 m long and have a small head and brown scales.

Fun Fact: Mole snakes don’t do a lot of burrowing themselves, instead they steal burrows from rodents.

Molossian hound

The Molossian hound was a huge dog breed from ancient Greece. Their size and ferocity was mentioned in numerous classical texts and they were incredibly large and popular animals.

Fun Fact: Some believe the modern mastiff, a huge guardian dog, is a descendent of this giant breed.

Mollusk

Molluscs are a diverse group of invertebrates that include snails, clams, octopuses, and squid. They are the second-largest phylum of invertebrates.  

Fun Fact: These are ancient and diverse animals, ranging from the humble garden snail to the giant squid and Pacific octopus.

Molly

Mollies are a genus of freshwater, brackish and saltwater fish native to the Americas. aquariums. They are very varied in colour and are common in aquaria.

Fun Fact: Some mollies have evolved to tolerate high levels of hydrogen sulfide so can live in extreme environments.

Monarch Butterfly

Monarch butterflies are iconic flying insects from the Americas known for their orange and black wings, epic migrations, and reliance on milkweed plants for breeding and feeding.

Fun Fact: The Monarch migration is so long it takes four generations to accomplish!

Mongoose

Mongooses are small carnivorous mammals found in Africa, Asia, and southern Europe. They come in a range of sizes and colours, from the dwarf mongoose to the white-tailed mongoose.  

Fun Fact: These little killers have evolved a special chemical defence against snake venom. A polypeptide in the animal prevents alpha-neurotoxins from binding and helps them survive bites.

Monitor Lizard

Monitor lizards are very large lizards in the Varanus genus. They’re recognised for their elongated bodies, powerful jaws, and forked tongues used for sensing prey and environment.

Fun Fact: Monitor lizards are warm-blooded and can actively hunt their prey. Across their range, they fill niches more commonly filled by mammals.

Monkey

Monkeys are simian primates found in various habitats worldwide. They’re primarily found in tropical regions, and usually in trees. Almost all have tails and are generally intelligent.

Fun Fact: Cladistically, humans are monkeys. Behaviorally, too, especially in the juveniles.

Monkeyface Prickleback

Monkeyface pricklebacks are unfortunate-looking animals from the East Pacific. They are elongated and dark, with upturned mouths and bulging eyes. They usually get to no more than 75cm and 2kg.

Fun Fact: This fish has all the looks of an eel, but is in fact in the scorpionfish order.

Monkfish

Monkfish, also known as frogfish and sea devils, are bottom-dwelling anglerfish found in deep-sea and coastal waters. They are flat with very large mouths, and dark skin and are as ugly as you’d expect from an angler.

Fun Fact: These fish spend most of their time covered in sediment, waiting to ambush fish. But there are reports of some sitting at the sea surface after a storm, catching sea birds.

Monocled Cobra

Monocled cobras are highly venomous snakes found in South and Southeast Asia, named for the distinctive “monocle” eyespot on the back of their hoods. They grow to about 1.5m long.

Fun Fact: Some populations of this species can spit venom, while others haven’t figured out how to do that yet.

Monte Iberia Eleuth

Monte Iberia Eleuths are very tiny rain frogs endemic to Cuba. They’re 1cm long, black, with yellow lines from the nose down each side.  

Fun Fact: These tiny frogs are quite toxic, so you shouldn’t eat them. They develop directly from eggs to adults, skipping the tadpole stage.

Moon Jellyfish

Moon jellyfish are 40cm, translucent cnidarians found all over the Northern Hemisphere. They can barely swim, so drift around with the currents.

Fun Fact: Unlike many jellyfish, these don’t have long tentacles. They have just a ring of short, venomous danglies around the bell. Their venom doesn’t affect people.

Moonglow Boa

Moonglow boas are a popular morph of boa constrictors, named for their pale, almost ghostly appearance. They’re not found in the wild.

Fun Fact: These boas are both hypo-melanistic albino and anerythristic, meaning they have no black or red pigment. Genetically, that’s a very rare combination of traits.

Moorhen

Moorhens, or marsh hens, are medium-sized water birds. They have dark plumage with a red beak and yellow feet and live near freshwater marshes and ponds across Europe, Asia and Africa.

Fun Fact: These birds aren’t all that great at flying, yet the common moorhen still manages to complete a 2,000km migration from Siberia to its Wintering grounds.

Moose

Moose, originally known as elk in Europe, are large herbivorous deer found in North America and Eurasia. They are well known for their massive size, broad antlers (in males), and being able to chase you down and stomp you dead.

Fun Fact: Moose are excellent swimmers and can dive underwater to feed on aquatic plants, using their long legs and buoyant bodies to navigate through lakes and rivers. They can close their nostrils when feeding underwater.

Moray Eel

Morays are a family of eels found all over the world. They’re elongated, snake-like fish with scaleless bodies, strong jaws, and often colourful patterns.

Fun Fact: These eels are known to be quite friendly and curious in some settings and will let divers pet them. But they can also bite off your thumb, so be careful.

Morpho

Morpho butterflies are a genus of large, beautifully iridescent butterflies found in Central and South America. They have shimmering wings of blues and greens, and some are orange or brown.

Fun Fact: The brilliant colour of Morpho butterflies’ wings is not due to pigment but rather the microscopic structures that refract light, creating the vibrant iridescence.

Moscow Watchdog

Moscow watchdogs are large, Russian guard dogs originally bred from the Caucasian shepherd and the St. Bernard for guarding purposes. They weigh more than 55kg and look a lot like St Bernards in colour.

Fun Fact: Moscow watchdogs are intimidating in their size but they’re said to be good companions if socialized early.

Mosquito

Mosquitoes are small flying Dipteran insects found worldwide, infamous for being the most annoying animal on the planet and killing billions of people.

Fun Fact: Only female mosquitoes bite to obtain blood, which provides essential nutrients for egg production, while males feed on plant nectar. Further, only 6% of the 3,600 species bite humans at all.

Moth

Moths are nocturnal insects closely related to butterflies, known for their scaled wings, varied colours, and often cryptic patterns for camouflage and the way they flap about in your face at night sometimes.

Fun Fact: There are a ridiculous number of moth species at around 200,000. Yet, we still don’t really know what they want.

Mountain Beaver

Mountain beavers, also known as Aplodontia, are rodent species native to the West Coast of North America. They’re dark grey or brown and weigh up to a kilo. Importantly, the penis is about 4.5cm long.

Fun Fact: Despite their name, mountain beavers are not beavers at all, and are more closely related to squirrels. They don’t do anything beavers do except bite you when you try to pick them up.

Mountain Bluebird

Mountain bluebirds are beautiful blue thrushes found in western North America. They grow to about 18cm long and breed all the way up into Canada and Alaska.

Fun Fact: Mountain bluebirds are cavity nesters, often using abandoned woodpecker holes or nest boxes for breeding and raising their young.

Mountain Cur

Mountain curs are versatile, short-coated working dogs originally from Europe but now bred in the southern United States. They’re known for their intelligence, athleticism, and loyalty to their owners.

Fun Fact: Mountain curs specialize in chasing animals up trees. They were originally bred for this and can be used to hunt or do assessments on arboreal animals like squirrels.

Mountain Feist

Mountain Feists, or Treeing feists, are small to medium-sized hunting dogs from the southwestern US. They’re used to hunt small game and are known for their agility, stamina, and treeing abilities, making them popular among hunters for hunting small game.

Fun Fact: These dogs became extremely rare in the ‘80s and a small group of fans teamed up to ensure the line didn’t disappear.

Mountain Gorilla

Mountain gorillas are huge primates found in the mountainous forests of Central Africa. They look like enormous, hairy humans, which is more or less what they are.

Fun Fact: Mountain gorillas are the largest primates on the planet, yet probably the least violent. Dominance is mostly maintained with diplomacy and some stern looks, though fights do occur.

Mountain Lion

Mountain lions, also known as cougars or pumas, are large felids native to the Americas. They’re solitary and stealthy hunters and the second-largest cat in the Americas after the Jaguar.

Fun Fact: It’s said that mountain lions can leap 5.5 meters off the ground into a tree. This is almost certainly exaggerated but they are incredibly agile and can leap great distances.

Mourning Dove

Mourning doves are medium-sized, elegant and understated pigeons found throughout North and Central America, named for their mournful cooing calls. They’re successful as a species and can fly very fast.

Fun Fact: Ironically, this bird is also known as the turtle dove – a symbol of new love, weddings and cheesy romantic songs. Presumably, it shows up again when one of the couple dies.

Mourning Gecko

Mourning geckos are small, nocturnal lizards native to Central and Southeastern Asia. They’re good climbers and grow to about 10cm long with grey or tan skin.

Fun Fact: Mourning geckos are almost all female. They just ditched the males and figured out how to reproduce without them.

Mourning Warbler

Mourning warblers are small, plump migratory songbirds found in North and South America. They’re yellow underneath and olive green on top.

Fun Fact: Mourning warblers breed in dense thickets and wetlands in southern Canada and then migrate to Central America and northern South America for Wintering.

Mouse

Mice are small rodents found all over the world. They’re one of the most successful groups of animals, thriving in a multitude of environments due to their adaptability, social behaviours and intelligence. 

Fun Fact: Like rats, mice are playful and friendly animals who learn quickly and can be taught to do tricks.

Mouse Spider

Mouse spiders make up a genus of astonishing 3cm long spiders found in Australia. They’re stocky, mostly hairless, black or purple, and have enormous fangs – sometimes blood red.

Fun Fact: These spiders dig burrows as deep as 30cm covered with a trapdoor, where the females will stay and wait for males to find them.

Mouse-Deer

Mouse-deer, also known as chevrotains, are a family of small ungulates found in Asia and Africa. There are ten species, all small at around 30cm tall.

Fun Fact: Mouse deer are the smallest hoofed mammals and spend most of their time alone or in pairs.

Mozambique Spitting Cobra

Mozambique spitting cobras are highly venomous African cobras. They’re darkly coloured, grow up to a meter long, and have fiery red and black patterns on their necks, which they expose as a threat.

Fun Fact: Mozambique spitting cobras can accurately spit venom up to 3 meters away. Or it might bite without spitting, or sometimes it’ll just play dead and hope you leave it alone.

Mud Dauber

Mud daubers are solitary wasps from one of two families, named for building mud nests.  They’re found in warm countries all over the world.

Fun Fact: When building their mud nests, the wasps will vibrate their wings to compress air out of the mud and make it stiffer and stronger.

Mud Snake

Mud snakes are non-venomous, semi-aquatic colubrid constrictor snakes found in North America. They are gloss black with smouldering orange/red patterns reaching up from beneath. They grow to 1.5 meters long.  

Fun Fact: These snakes rarely leave the water at all, though will dig themselves into mud burrows on the edge of streams.

Mudi

Mudis are Hungarian herding dogs used for herding. They’re almost border-collie-shaped with a shaggy coat and stockier build.

Fun Fact: The intelligence, high energy requirements and athleticism of this breed make them very good at playing frisbee.

Mudpuppy

Mudpuppies, also known as waterdogs, are a genus of aquatic salamanders found in North America.  They usually grow to no more than 25cm and there are seven known species.

Fun Fact: Like axolotls, these salamanders retain juvenile traits into adulthood. They have external gills and no eyelids.

Mudskipper

Mudskippers are fish that don’t know they’re fish. They live in coastal Africa and flop about in the mud like amphibians.

Fun Fact: Mudskippers can almost breathe like a land animal. They have highly absorbent mouths and skin, meaning they can take a big gulp of air and extract the oxygen from it while they’re out of the water.

Mule

Mules are hybrid animals resulting from the crossbreeding of a male donkey and a female horse. They’re bred for the endurance of a donkey and the strength of a horse.

Fun Fact: Donkeys and horses have differing numbers of chromosomes, making it very strange that mules can exist in the first place. But because of this, mules are always sterile.

Mule Deer

Mule deer are large North American deer, very much like the white-tailed deer, but with large ears that give it the name.

Fun Fact: This is a deer species that loves to pronk. Like antelope, they jump vertically in the air with all four limbs straight out.

Mulga Snake

Mulga snakes, also known as king brown snakes, are venomous elapid snakes found in Central Australia. They grow up to 3.3 meters long and weigh up to 6kg.

Fun Fact: This is Australia’s biggest venomous snake, though it’s not as deathly dangerous as many other species.

Mullet

Mullets are a family of marine and freshwater fish found worldwide. There are over 70 species, most of which are elongated and silver and feed on detritus.

Fun Fact: Mullets are currently classified as the only family in the order Mugiliformes, but this is still a matter of contention.

Muntjac

Muntjacs are tiny deer found in Asia. They’re shy, small and sometimes have fangs. They can also bark

Fun Fact: Muntjacs are often considered primitive deer on account of them having small antlers and prominent tusks, which are used in the way bigger species use antlers.

Muscovy Duck

Muscovy ducks are large waterfowl native to the Americas but are now found all over the world. They’re brightly coloured with white plumage contrasted by black patches and a red face.

Fun Fact: Muscovy ducks have claws on their feet and wings, making them a lot more dangerous to cuddle than your average duck.

Musk Deer

Musk deer are small, solitary ungulates found in Asia, named for their musk-producing glands and known for their long tusks.

Fun Fact: These aren’t real deer, and are in a separate family that’s more closely related to the bovids.

Muskellunge (Muskie)

Muskellunge, commonly known as muskies, are large freshwater predatory fish native to North America. They look like pike but can grow to 30kg.  

Fun Fact: Muskellunge are powerful apex predators in their habitats and will readily attack prey much larger than other fish their size would dare to.

Muskox

Muskoxen are huge, shaggy Arctic Bovids. During the rut, males absolutely stink, which is where the name comes from. They have thick fur, and distinctive curved horns, and are well-adapted to cold environments.

Fun Fact: These lumbering animals can really move when they want to. They can potentially run at 60km/h.

Muskrat

Muskrats are semi-aquatic beaver-like rodents native to North America and introduced elsewhere. They have webbed feet, and the ability to build lodges and burrows in wetland habitats.

Fun Fact: Muskrats aren’t rats or beavers but in the lemming family.

Myna Bird

Myna birds are starlings from Southern Asia and can be found as an introduced species in North America and Australasia. They’re medium-sized and typically eat insects and fruit.

Fun Fact: Some mynas are “talking birds”, able to imitate human speech and other sounds.

Myrmecophagidae

Myrmecophagidae is a tiny family of anteaters, comprised of only three species: the giant anteaters and the two Tamandua species. They’re an ancient lineage whose name literally translates to “ant eaters”.

Fun Fact: Myrmecophagidae are part of the Xenartha clade, and the Pilosa order, sharing it with the extant sloths and the extinct giant sloths.

What Other Animals Begin With ‘M’?

That completes our list of animals that begin with the letter M.

Hopefully you’ve learned a few new ones, but are there any that we’re missing in our list that you would like to see covered?

If so, get in touch. Please see our Animal A-Z list for animals that start with different letters.