EPOW - Ecology Picture of the Week

Central African Mud Turtle (Pelusios chapini), family Pelomedusidae
Bobangi Village, Ubange River, Democratic Republic of the Congo

Explanation:  It took us over a week to reach here from the cities of Kinshasa and then Mbandaka, to the village of Bobangi along the Ubange River that forms the border between Republic of Congo and the Democratic Republic of the Congo in central Africa.  Our expedition arrived in pirogues (dugout canoes) a few days ago, on a project to help local villagers develop their own forest resource management plans.  As a vote of thanks in this village, as we leave, the village chief and his council present us with several gifts of plants and animals, including this turtle.

The back shell or carapace of the Central
African mud turtle.  Note the string used to 
restrain the animal from escaping.

Just a turtle?  This is a Central African mud turtle, which was captured here along the banks of the Ubange River.  The species is not well studied and, in fact, these may be some of the first photos in its native environment.  

Side view of the carapace.

The Central African mud turtle belongs the family of turtles called Afro-American side-necked turtles.  Indeed, as this turtle pulls its head into its shell, it turns the head sideways, and then the lower shell (the plastron) hinges upward to close off access by predators to the head and neck.  

The "side-necked" manner in which the head
is pulled into the shell.

View below ... the plastron.  Note that it is concave,
signifying that this is a male.  The concave shape helps
the male mount the female during mating.  Now you know.
The plastron also is hinged so that the front portion
can swing upwards and close up the opening to the head.

In all, there are some 17 species of Pelusios (in general called African hinged terrapins).  

On some turtles you can count the number of "rings" on
the scutes (shields) of the shell, and thereby estimate
the turtle's age.  How old might this turtle be, assuming
that one line equals one year?

This species is Pelusios chapini, although in 1977 taxonomists combined it with the species Pelusios castaneus, the West African mud turtle, and then later split it out as a subspecies.  More recent analysis (in 1983), though, put it into its own species, and therein may lie some confusion.  Most specimens of "Pelusios chapini" found in zoos likely are misidentified and not this species, which makes this finding and these photos more important.  

The abundance and viability status of this turtle species throughout its range in central Africa is essentially unknown.  Four other species of Pelusios (P. adansoni, P. castaneus, P. niger, and P. gabonensis) from Ghana are listed as CITES Category III species (Ferry Grunewald, pers. comm.).  CITES is an international convention to protect wildlife species, and category III species are those populations of species and subspecies of wildlife that highly need local protection. 

In Bobangi Village, this turtle, like most other wildlife, is hunted, trapped, or netted for food to eat or sell as bushmeat.  Impacts of such use on local populations of this species are unknown.
 

Information:
     Marcot, B. G. 2005. Two turtles from western Democratic Republic of the Congo: Pelusios chapini and Kinixys erosa. World Chelonia Trust Newsletter 8:1-2,8.  [View as PDF file.]

Update:
     There are now 18 recognized species of Pelusios, as a new species, Pelusios cupulatta, has been recently (2003) described by Bour and Maran (Ferry Grunewald, personal communication, 10 February 2006). 

Acknowledgment:
     My thanks to Ferry Grunewald for his help with species identification and further information.  Mr. Grunewald is a member of the Dutch Turtle & Tortoise Society, Nederlandse Schildpadden Vereniging (NSV, http://www.trionyx.nl) and co-studbook keeper for Pelusios species and Siebenrockiella crassicollis for the European Studbook Foundation (ESF, http://www.studbooks.org), and imminently knowledgeable on Pelusios species (http://www.pelusios.com).  My thanks also to Darrell Senneke, Director of World Chelonia Trust; Hynek Prokop of Czechoslovakia; and Dr. Harald Artner of Austria, also for helping with identification.