Euphrates softshell turtle  (Rafetus euphraticus)

The Euphrates softshell turtle is classified as Endangered (EN) on the IUCN Red List (1).

The Euphrates softshell turtle (Rafetus euphraticus) is one of the least known species of the Trionychidae family (3). The name of this species comes from the fact that the carapace does not have horny plates like many turtles, and is instead made up of a tough, leathery skin which is covered with numerous hard tubercles (4).

The roundish, oval carapace of the Euphrates softshell turtle is dark olive-green (2) (4), with small whitish spots (4).

The Euphrates softshell turtle is endemic to the Tigris and Euphrates rivers and their tributaries, in south-eastern Turkey, north-eastern Syria, Iraq and south-western Iran (1) (2) (3) (5).

In Iran, the range of the Euphrates softshell turtle is limited to the rivers of Khuzestan Province (3) (5).

The Euphrates softshell turtle is a semi-aquatic species (1), with the relatively calm tributaries of larger rivers being its preferred habitat. This species is also found in oxbow lakes, which are formed when a wide meander from the main part of the river is cut off (6).

The Euphrates softshell turtle is a thermophilic species, which means it prefers warmer temperatures (6). Being mostly aquatic, this species is an agile swimmer, but it can also move rapidly on land (4).

The Euphrates softshell turtle is largely carnivorous (6), and feeds on fish, molluscs, frogs and crustaceans (4). It sometimes eats plant material (6), and has even been reported to feed on carrion (7).

Very little is known about the reproductive biology of the Euphrates softshell turtle. However, studies have shown that, in the upper part of the Euphrates river, eggs are laid from the end of May to early June. The Euphrates softshell turtle digs a nest chamber in sand that is between 13 and 50 centimetres deep. The eggs are deposited in the bottom of the chamber, and have a round, hollow space above them (8).

Clutches of the Euphrates softshell turtle usually contain about 30 hard-shelled, spherical eggs, each of which weighs approximately 13.5 grams (8).

Habitat destruction, caused by damming projects along the Tigris and Euphrates rivers, is a major threat to the Euphrates softshell turtle (2) (6) (8).

Dams cause changes in the environment by decreasing water temperatures, and by flooding sandy banks which are necessary for the Euphrates softshell turtle to nest on (6). It is thought that a population of this species was driven to extinction near Halfeti, Turkey, as a result of a drop in water temperature due to the construction of a dam 60 kilometres upstream (8).

An imminent threat to the Euphrates softshell turtle is the planned construction of a large dam, Ilisu, which will flood approximately 300 square kilometres of land along more than 136 kilometres of the Tigris river. The dam will significantly reduce the number of nesting and basking areas available for this species (8).

Pollution and poaching are also threats to the Euphrates softshell turtle (3) (5).

Proposed conservation measures include further studies into the biology and habitats of the Euphrates softshell turtle, as well as into the relationship between this species and local communities (5).

Find out more about freshwater turtles:

• IUCN/SSC Tortoise and Freshwater Turtle Specialist Group:
  http://www.iucn-tftsg.org/

Learn more about reptile conservation:

• International Reptile Conservation Foundation:
  http://www.ircf.org/

Find out more about the habitat of this species:

• ARKive - Mediterranean Basin:
  http://www.arkive.org/eco-regions/mediterranean-basin/