Yellow Mud Turtle

1 Overview

The yellow mud turtle, also called the yellow mud turtle or yellow ‘egg’ turtle, is one of the common mud-turtle species. The carapace is yellow with large, flat scutes edged in black, giving a very pretty look. It is semi-aquatic but prefers the water, likes meaty food and has a simple diet.

Chinese Name: Yellow Mud Turtle

Also called: Yellow Mud ‘Egg’ Turtle

Binomial: Kinosternon flavescens

Distribution: from northern Nebraska south to Texas, the eastern and southern parts of New Mexico, southeastern Arizona, and into Mexico; isolated populations on the edges of Illinois and Iowa.

Reproduction: oviparous. In New Mexico they lay in June; a clutch has 1-6 eggs (usually 4), elliptical with a hard shell. Juveniles reach maturity in 6-7 years.

Habits: they like quiet, slow water with a muddy or sandy bottom. In colder months they hide under brush or leaf litter, in tree hollows, in muskrat dens, or buried in mud underwater. Generally shy, they rarely attempt to bite.

Size: 9-16.2 cm; carapace olive to dark brown, smooth and unkeeled, usually rather flat, with black-edged scutes.

Diet: worms, arthropods, snails and tadpoles. Semi-aquatic but water-leaning.

Kingdom: Animalia

Phylum: Chordata

Subphylum: Vertebrata

Class: Reptilia

Order: Testudines

Family: Kinosternidae

Genus: Kinosternon

2 Physical Characteristics

It is Iowa’s second-smallest water turtle, just larger than the musk turtle. Hatchlings are under 2.5 cm. There are yellow spots on the shell edge and no vertebral ridge. The adult carapace is only about 13 cm long. The carapace is dark, unmarked, very flat on top and elliptical. The plastron is much better developed than the stinkpot’s: a pale-yellow base with several lines and no spots of any size; the pectoral, abdominal and femoral scutes are joined by two ligaments.

3 General Care

This turtle is dormant for much of the year. When the climate changes markedly it seeks natural cover — stumps, the base of bushes, dry leaves and logs. Some bury themselves in sand or soil, especially during winter and summer dormancy. One factor that brings them back to activity is warm rain, which refills dried ponds or streams. Sometimes they migrate long distances to find water.

4 Captive Habitat

The quality of the environment affects not only health but also appearance — a good setup keeps the carapace glossy, just as people care for their looks.

Wild environment: marshes, creeks, ponds, lakes, reservoirs, semi-arid grassland, open woodland and dune surroundings; it likes ponds with a muddy or sandy bottom and abundant aquatic plants. Its range is wide and density still high, so apart from humans there is no major threat; populations remain in northwestern Nebraska, southeastern Iowa and southeastern Illinois.

Captive setup: a breeder tank about 100 x 50 x 50 cm. Because it enjoys basking, design a basking platform. Keep land-to-water at 1:2. It is not very fond of high heat and has a summer-dormancy habit, with about 25°C water ideal — southern keepers take note! Over the keeping period you will find it adapts to its surroundings and changes colour; by this trait, use a white container for captive-bred individuals to make the colour more vivid.

5 Feeding

There are many food choices. In the wild it leans toward meat — catching insects and molluscs — while in captivity people often use food to change the carapace colour and make it more vivid.

Diet: it is a carnivore. Food includes insects, molluscs, crustaceans, amphibians, annelids, nematodes, leeches, flatworms, centipedes, spiders, aquatic plants and carrion. Those under 5 cm eat mainly small aquatic insects, algae, carrion and dead fish; those over 5 cm show dietary variety. It usually forages on the riverbed bottom but sometimes on shore or the surface; a keen sense of smell helps it find food underwater.

For a brighter carapace, steady pigment intake is needed. Many choose shrimp for the astaxanthin that accumulates slowly in the body and shows in the patterns and skin — some patterns emerge gradually as the turtle grows, so it is a long process; do not rush it. Pursuing colour by feeding only shrimp will only cause health problems.