Emys sinensis Gray, 1834, China. No subspecies are recognized.
OTHER COMMON NAMES
This is a medium-sized geoemydid turtle (up to 9 in [24 cm] carapace length) with the plastron rigidly attached to the carapace and lacking a hinge; a fourth vertebral scute that is wider than long; the crushing surfaces of the upper jaw are broad along their entire length, with a single, well-developed medial ridge present on each surface; five claws on the forefoot; and numerous dark-bordered, narrow yellow stripes on the head and neck.
Taiwan, southern China (including Hainan Island), and northern Vietnam.
This species inhabits slow-moving lowland freshwater habitats, from ponds and rivers to marshes and human-made canals.
This is an aquatic turtle that often climbs out of the water to bask. Its behavior is in great need of study.
The only detailed study of this turtle's diet is from Taiwan; this study suggests that significant dietary differences exist between the sexes. Juveniles of both sexes tend to be carnivorous, eating primarily insects along with plant roots, shoots, and leaves. The males remain primarily carnivorous into adulthood, consuming mainly dipteran (mosquito) larvae and other insects, as well as some plant leaves, seeds, and roots. The females become increasingly herbivorous as they mature, feeding primarily on the leaves of terrestrial plants that grow along riverbanks, but also occasionally eating insects (especially dipteran larvae).
Males apparently mature after three to four years and females after five to eight years. On Taiwan the females apparently nest from April to early June, although they are reported to nest from April to August on mainland China. On Taiwan the relatively deep nests (6-9 in [15-22 cm]) are constructed on open sandbars along the river or in open areas away from the water. The clutch size ranges from seven to 17 eggs on Taiwan, whereas three to 14 eggs per clutch are apparently laid on mainland China. The eggs are elongate, brittle-shelled, and on Taiwan measure 1.2-1.5 in (30-39 mm) in length, 0.7-0.9 in (18-22 mm) in diameter, and 0.2-0.4 oz (6-10 g) in mass. Three eggs laid in captivity by a female from Hainan Island were 1.6 X 1.0 in (40 X 25 mm), suggesting some geographic variation in reproductive parameters. The effect of temperature on sex is unknown. This species apparently hybridizes with at least the Chinese three-striped box turtle (Cuora trifasciata) and the Annam leaf turtle (Mauremys annamensis).
This species is listed as Endangered on the IUCN Red List. It is surprisingly tolerant of polluted aquatic systems.
These turtles are frequently consumed by humans and small numbers still enter the pet trade. They may be ranched in impoundments on Taiwan and Hainan Island for commercial purposes. Studies have shown that plastrons of this species are frequently sold fraudulently as "tortoise shell" in medicine shops. ♦
Was this article helpful?