Reptiles
Spiny Softshell Turtle
Apalone spinifera · also called spiny softshell turtle, spiny softshell, pancake turtle
The spiny softshell turtle looks like someone flattened an ordinary turtle and swapped its shell for a leather pancake. It has a snorkel for a nose, it breathes through its skin and throat, and it spends much of its life buried in river sand with only its nostrils showing.
Overview
Spiny softshells live in rivers, streams, lakes, and impoundments across the central and eastern US and into southern Canada, favouring sandy or muddy bottoms. They are carnivores, eating crayfish, insect larvae, mussels, and small fish. The shell is a flat, flexible, leathery disc with no hard plates and small cone-like spines along the front edge; females reach 54 cm, males far less.
Snorkel and skin-breathing
A long flexible snout with tube nostrils lets the turtle breathe from the bottom of shallow water without moving. It also extracts dissolved oxygen through its skin and through blood-rich sacs in its throat, so it can stay submerged for hours while active — and all winter while dormant.
Fast and sharp
Losing the heavy shell makes it one of the fastest freshwater turtles. It relies on speed and burial rather than armour, but a cornered adult has a long neck, sharp hidden jaws, and claws, and bites hard.
Status
The spiny softshell is Least Concern and widespread, though some Canadian and edge populations are declining from river alteration and nest predation.
Spiny Softshell Turtle: common questions
Why does a softshell turtle have a soft shell?
Its shell has lost the hard outer scutes (the horny plates) and much of the bony under-structure that a typical turtle has, and what remains is covered by tough, leathery skin. The carapace is flattened, disc-shaped, and slightly flexible around the edges. The trade-off is less armour but much less weight and drag, which makes the spiny softshell one of the fastest-swimming freshwater turtles and lets it bury quickly and completely in sand. It compensates for the reduced protection with speed, a very long reach, powerful jaws, sharp claws, and a strong tendency to flee or hide rather than stand and fight, though a large one that cannot escape will bite savagely.
How does a spiny softshell turtle breathe underwater?
In two ways beyond simply holding its breath. First, its skin is thin and well supplied with blood vessels, and dissolved oxygen from the water diffuses directly across it into the bloodstream. Second, it has folded, blood-rich sacs in the lining of its throat (pharynx), and by pumping water in and out of its mouth it passes that water over these surfaces to extract oxygen — a process called pharyngeal or buccopharyngeal respiration. Together these let the turtle stay submerged for hours while active, and for months while dormant on the bottom through winter, surfacing only occasionally or not at all. The snorkel-like snout handles the rest, letting it take a quick breath of air without lifting its head clear of the water.
Are spiny softshell turtles dangerous?
They are not aggressive toward people in the water and will almost always swim away, but a large female out of the water or being handled is genuinely capable of hurting you. The neck is remarkably long and can whip back over the shell to reach a hand holding the rear edge; the jaws, concealed behind soft lips, are sharp and strong enough to give a deep cut or crush a finger; and the claws can scratch badly. There is no venom, and there are no reports of serious unprovoked attacks — the risk is entirely to someone picking one up. The safe way to move one is by the very back of the shell or the tail base, well clear of the head's reach.
What is the difference between a spiny softshell and a snapping turtle?
They are not closely related and look quite different once you know what to check. A snapping turtle has a hard, ridged, bony shell, a massive head, a long saw-toothed tail, and a hooked beak, and it is a heavy, slow ambusher. A spiny softshell has a flat, round, leathery, scute-less shell, small cone-like bumps along the front edge, webbed feet, a pig-like snorkel snout, and a smooth short tail, and it is a fast, active swimmer that buries in sand. Both bite hard and both are found in similar rivers and lakes, but the softshell relies on speed and concealment while the snapper relies on armour and a powerful jaw.