Midland Smooth Softshell
Photo Copyrighted by J.S. Aber
SCIENTIFIC NAME: Apalone mutica mutica
DESCRIPTION: The midland smooth softshell turtle (Apalone mutica mutica) is one of the two subspecies of smooth softshell turtles (Apalone mutica) in the Family Trionychidae. They are very similar to the other subspecies of smooth soft shell turtles (Apalone mutica calvata) with the most notable differences being observed in the range of the two subspecies and the habitat in which they are found. Midland smooth softshell turtles are a medium to large freshwater turtle with an ovoid carapace that lacks spines on the front edge. Carapaces are covered by skin instead of the hard scutes generally associated with many turtle species. The species shows sexual dimorphism with females having a carapace length of 6 to 16 inches and males having a length of 4.5 to 11 inches. The coloration of the carapace is generally tan or brown in females and brown or gray in males. Both sexes have dark markings on the carapace, but the female’s markings may be in a blotchier pattern. The head, tail, and limbs have a similar colorization to the carapace. This species also has a tubular snout with round nostrils that lacks a septal ridge.
DISTRIBUTION: The midland smooth softshell turtle is native to the temperate climates of North America with a historical range extending throughout the central and south-central portions of the United States from Pennsylvania to New Mexico. However the species is thought to be extirpated from Pennsylvania.
HABITAT: Smooth softshell turtles are the most aquatic of all North American turtle species. They can be found in riverine and stream systems throughout their range. Unlike the very similar Gulf Coast smooth softshell turtle, the midland soft shell turtle can be found in areas with standing water, such as ponds and lakes, as well as streams and river systems with flowing water. This species prefers an area with a sandy or muddy substrate and will avoid areas with a rocky substrate.
FEEDING HABITS: Although mostly carnivorous, smooth softshell turtles also consume some plant materials. They are an ambush predator using their long neck to grab passing prey while lying concealed in the substrate. They are also known to hunt out of water using the same technique and to use their nose to find food hidden in the substrate. Females generally will hunt in deeper waters, while the males will utilize the shallow waters near the shore.
LIFE HISTORY AND ECOLOGY: Midland smooth soft shell turtles spend the majority of their time in the water. Its morphological adaptations allow for it to stay submerged for extended periods of time often buried in the substrate. Smooth softshell turtles hibernate in the winter months by burying themselves in the substrate underwater. Breeding in this species is believed to occur in April to June. One to three clutches can be laid with clutch sizes ranging from 1 to 33 eggs. Clutches produced in the later times of the season usually contain fewer eggs. Nests are usually located on sand bars with little or no vegetation within 60 feet of the water’s edge. The female will usually burrow a tunnel and place herself at the opposite end of the nest. Eggs will hatch in 8 to 12 weeks after they are laid. The young are precocial, able to feed and care for themselves, once they have hatched. Males and females become sexually mature at four and nine years of age, respectively.
Smooth Softshell Turtle. Animal Diversity Web. University of Michigan Museum of Zoology.
Smooth Softshell Turtle. IUCN Red List of Threatened Species.
Smooth Softshell Turtle. ENature.com.
AUTHOR: Justin Brock, Wildlife Biologist, Alabama Division of Wildlife and Freshwater Fisheries, December, 2012