Yellow Mud Turtle

Photo of a yellow mud turtle.
Species of Conservation Concern
Scientific Name
Kinosternon flavescens
Kinosternidae (mud and musk turtles) in the order Testudines (turtles)

The yellow mud turtle is a small, olive to dark-colored, semiaquatic turtle with a restricted range. It is considered an endangered species in Missouri. The upper shell is somewhat flattened and is olive brown, dark brown, or black, sometimes with dark brown edges of the scutes. The limbs and upperparts of the head and neck are olive; there is yellow on the chin and neck and along the edge of the upper shell. The lower shell is yellow and brown. The tail of the male ends in a clawlike, horny tip. Mud turtles give off an offensive, musky odor when captured.

Similar species: The closely related Mississippi mud turtle (K. subrubrum hippocrepis) is found only in the Bootheel.


Upper shell length: 4 to 5 inches.

Where To Find
Yellow Mud Turtle Distribution Map

The yellow mud turtle occurs in a few counties in southwestern Missouri and in the Kansas City area, and in a few marshes in far northeastern Missouri. Missouri’s mud turtles are quite separated geographically.

The yellow mud turtle prefers a sandy habitat and spends as much time on land as in the water. Its aquatic habitats include rivers, sloughs, ponds, water-filled ditches, marshes, oxbow lakes, and flooded fields. Streams or ponds with muddy or sandy bottoms are preferred. It spends the winter as well as the hot months of summer buried in mud or sand on land, and moves overland from pond to pond.

A variety of aquatic animals and some plants are consumed, including insects, snails, crayfish, tadpoles, and dead fish.

The yellow mud turtle is listed as endangered in the state of Missouri. Because of its limited range, extreme rarity, habitat needs, and other factors, it is in danger of being extirpated from our state.

At one time, two subspecies of yellow mud turtle, Kinosternon flavescens, were recognized, and both occurred in Missouri. The yellow mud turtle (K. f. flavescens) occurred in southwestern Missouri and in the Kansas City area, while the Illinois mud turtle (K. f. spooneri) was found in extreme northeastern Missouri. Scientists, however, determined that the Illinois mud turtle wasn't different enough to be considered a valid subspecies, so at this point, only the yellow mud turtle is recognized in our state.

Life Cycle

This species is active April–October. Courtship and mating occur from late April to mid-May. In June or July, the female digs a nest in a usually sunny spot with well-drained sand or soil, and lays 6–8 eggs. She may not lay all her eggs at once but instead wait a day or so and make another nest. This can keep a lucky nest predator from finding all her eggs. Hatching occurs from late August to mid-September. Young turtles hatching late in the season may stay in the nest until the next spring.

Turtles are important to humans symbolically. They represent patience, longevity, wisdom, and perseverance. They figure into hundreds of ancient myths worldwide. Each species has a unique character that humans can appreciate. Native Americans used turtle shells to make rattles.

As predators, they help keep populations of insects, snails, crayfish, and amphibians in balance. As scavengers of dead fish, they help to clean the water. As prey (for they are vulnerable as eggs and young), they feed animals ranging from insects to birds, snakes, and mammals.

Media Gallery
Similar Species
About Reptiles and Amphibians in Missouri
Missouri’s herptiles comprise 43 amphibians and 75 reptiles. Amphibians, including salamanders, toads, and frogs, are vertebrate animals that spend at least part of their life cycle in water. They usually have moist skin, lack scales or claws, and are ectothermal (cold-blooded), so they do not produce their own body heat the way birds and mammals do. Reptiles, including turtles, lizards, and snakes, are also vertebrates, and most are ectothermal, but unlike amphibians, reptiles have dry skin with scales, the ones with legs have claws, and they do not have to live part of their lives in water.