Geoemydidae

Class Reptilia Order Testudines Suborder Cryptodira Family Geoemydidae

Thumbnail description

A diverse family of hard-shelled turtles with a single articulation between the fifth and sixth cervical vertebrae, webbing between the toes, and posterior marginal scutes that extend up on to the suprapygal bone

Size

Up to 32 in (80 cm) carapace length and 110 lb (50 kg)

Number of genera, species

27 genera; 62 species

Habitat

Freshwater to coastal marine systems to primary and secondary forests

Conservation status

Extinct: 1 species; Critically Endangered: 13 species; Endangered: 18 species; Vulnerable: 11 species

Distribution

Eurasia and North Africa and the tropical Americas

Distribution

Eurasia and North Africa and the tropical Americas

Evolution and systematics

Formerly known as the Bataguridae, this family is most closely related to the tortoises of the family Testudinidae. Together these two families are next most closely related to the pond turtles of the family Emydidae. Fossils are known from as long ago as the Eocene. Geoemydid turtles previously were divided into two subfamilies based on the upper jaw width (i.e., wide alveolar crushing surfaces versus narrow ones). However, molecular studies have demonstrated that similarities in jaw width do not precisely reflect phylo-genetic relationships. Hence, no subfamilies currently are recognized.

Physical characteristics

The well-developed shell includes 24 marginal and 12 plastral scutes. The pectoral and abdominal scutes contact the marginal scutes. In addition, the posterior marginal scutes extend up on to the suprapygal bone. A single articulation is found between the fifth and sixth cervical vertebrae. Most included species have at least some webbing between the toes and some species have a hinged plastron. Sexual dimorphism is extraordinary in some species; for example, males of the Indian tent turtle (Kachuga tentoria) are usually less than 4 in (10 cm) in shell length, whereas females approach 12 in (30 cm).

Distribution

Europe and North Africa to southern China and the East Indies; the Americas from northern Mexico to Brazil and Ecuador.

Habitat

From almost any freshwater ecosystem to coastal marine systems to fully terrestrial in primary and secondary forests; mainly tropical and subtropical.

A Malayan box turtle (Cuora amboinensis) hatchling. (Photo by Henri Janssen. Reproduced by permission.)
A female black-breasted leaf turtle (Geoemyda spengleri). (Photo by Henri Janssen. Reproduced by permission.)
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