African helmeted turtle
|African helmeted turtle|
The African helmeted turtle (Pelomedusa subrufa), also known as the marsh terrapin, crocodile turtle, or in the pet trade as African side-necked turtle, is an omnivorous side-necked terrapin that naturally occurs in fresh and stagnant water bodies throughout much of Sub-Saharan Africa, and even in southern Yemen.
The Marsh Terrapin is typically a rather small turtle, with most individuals being less than 20 cm in carapace length, but one has been recorded with a carapace length of 32.5 cm. It has a black or brown carapace (shell). The tops of the tail and limbs are a grayish brown, while the underside is yellowish.
The male turtle is distinguished by its long, thick tail. A female tends to have a shorter tail and a broader carapace. A hatchling has a shell size of about 1.2 inches in length, and is olive to black in color. It also has two small tubercles under the chin and musk glands in the sides of the carapace.
Uniquely, Pelomedusa does not have a hinged plastron (lower shell). All the other species in the family Pelomedusidae, however, have this feature which they can, using muscles, close to cover their heads and front limbs. Unlike many chelonians, African helmeted turtles are able, when they find themselves upside down, to right themselves with a vigorous flick from their long muscular necks.
Recent genetic research suggests that Pelomedusa comprises at least 10 different species, and not only one as previously thought. In the past the physical differences between populations were not regarded as substantial enough to recognise more than one species.
The range of P. subrufa covers a large portion of Africa, from the Cape Peninsula to the Sudan. It can be found as far west as Ghana and as far south as Cape Town. It has also been found in Madagascar and Yemen.
They are semiaquatic animals, living in rivers, lakes, and marshes, and they also occupy rain pools and places that are fertilized.
Their preference seems to be for standing water, such as swamps, pans, dams and lakes. However they are found to a lesser extent along rivers. They are generally absent from regions that are mountainous, forested or desert.
The African helmeted turtle is omnivorous and will eat almost anything. Some of the main items in its diet are insects, small crustaceans, fish, tadpoles, earthworms, snails and vegetation. It may also feed on carrion. The fine claws on its feet help it tear its prey apart.
Groups of these turtles have been observed capturing and drowning larger prey such as doves when they come to drink; the commotion caused by these group attacks are often mistaken for crocodiles. All food is taken underwater to be eaten.
Several large mammals such as warthogs, Cape buffalo and Rhinoceroses have recently been documented utilizing the turtles to remove parasites at popular wallowing holes. One such incident in Hluhluwe-iMfolozi park involved two African helmeted turtles removing ticks and blood-sucking flies from the body of a wallowing warthog. Though the turtles probably do not have a symbiotic relationship with these animals, it is very likely that the buffalo, rhinos and warthogs seek them out and have learned to utilize them from past experiences. This behavior was documented for the first time in the September 2015 issue of Herpetological Review by Andy and Michelle Leighty Jones.
During wet weather these terrapins will often leave their water bodies and embark on long overland journeys. During exceptionally dry weather when their water bodies dry up, they will typically dig themselves into the ground and bury themselves until rains return; they have been known to spend months or even years in such a state. They will also hibernate during very cold weather, and aestivate during unusually hot, dry weather.
Courtship is held year round. The male will follow the female, nodding his head in front of hers. If she is not responsive, she will nip and snap and walk away. If she is willing, she responses by nodding her head or just standing still, so he can sit onto her. While mating both of the turtles shake their head.
African side-necked turtles are popular as a pet because of their unusual head tucking behavior.
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