Pelomedusidae

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Alternatively, "Pelomedusidae" may refer to the Pelomedusoidea. See below for details.
Pelomedusidae
Pelomedusa subrufa Beloa 070306.JPG
African Helmeted Turtle (Pelomedusa subrufa)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Superclass: Tetrapoda
Class: Reptilia
Subclass: Anapsida
Order: Testudines
Suborder: Pleurodira
Family: Pelomedusidae
Cope, 1868
Genera

Pelomedusa
Pelusios
Posadachelys

Synonyms

Pelomedusinae

The Pelomedusidae are a family of freshwater turtles native to eastern and southern Africa. They range in size from 12 to 45 cm (4.7 to 17.7 in) in shell length, and are generally roundish in shape. They are unable to fully withdraw their heads into their shells, instead drawing them to the side and folding them beneath the upper edge of their shells, and hence are called African side-necked turtles.

The family contains two living genera. They are distinguished from their closest relatives by a hinge in the front section of the plastron. [1]

Pelomedusidae spend most of their time in the mud at the bottom of rivers or shallow lakes, where they eat invertebrates, such as insects, molluscs, and worms. Many species aestivate through the dry season, burying themselves in the mud.[1]

Systematics and taxonomy[edit]

The related Podocnemididae are either treated as a distinct family, or as a subfamily (Podocnemidinae) in the Pelomedusidae. The African side-necked turtles are then also demoted to subfamily rank, as Pelomedusinae.[2]

As taxonomic rank is only meaningful as part of a sequence (a biological "family" has no fixed meaning on its own), both treatments are technically correct. Ultimately, the issue hinges upon the Austro-American sideneck turtles (Chelidae).[citation needed] These Pleurodira are less closely related to the Podocnemididae and Pelomedusidae than these are to each other.[citation needed] If all three are ranked as full families, the Chelidae are treated as a basal lineage, while the other two are united in the superfamily Pelomedusoidea.[citation needed] This treatment is preferred here, because it allows more convenient placement of prehistoric pleurodires (e.g. the Bothremydidae).

Footnotes[edit]

  1. ^ a b Obst (1998)
  2. ^ E.g. Obst (1998)

References[edit]

  • Obst, Fritz Jürgen (1998): [Pelomedusinae]. In: Cogger, H.G. & Zweifel, R.G. (eds.): Encyclopedia of Reptiles and Amphibians: 112-113. Academic Press, San Diego. ISBN 0-12-178560-2

External links[edit]