(Gray, 1831b)
Asian leaf turtle
Recognition
The oval carapace (to 26 cm) is slightly arched and contains a single medial keel. Vertebrals are usually broader than long, but the 2nd to 4th may be as broad as long. The posterior border of the carapace is serrated, and the scutes are gently textured, but may become more smooth with age. Carapacial color varies from light to dark brown, black, olive, or sometimes mahogany; narrow black radiations may be present. The adult plastron is notched posteriorly. The plastral formula is: pect > abd > an > fem >< gul > hum. The plastron varies from yellow or light brown, with dark radiations, to uniformly dark brown or black. The snout is slightly projected, and the upper jaw lacks toothlike projections on each side. Posteriorly, the head skin is divided into large scales; dorsally, it is reddish brown while the sides and jaws are darker brown. Head and neck are striated with reddish to orange, but these stripes may be faded or absent in older individuals. The chin is either striated or uniformly dark. Legs are light brown to cream with large transverse scales on the anterior surface.
Nakamura (1949), Stock (1972), and Killebrew (1977a) reported the karyotype of Cyclemys dentata is 2n = 52; 28 macrochromosomes (18 metacentric or submetacentric, 10 telocentric or subtelocentric) and 24 microchromosomes. Kiester and Childress (in Gorman, 1973) found it to vary between 50 and 52.
Females may grow larger than the males, but the males have longer, thicker tails.
Distribution
Cyclemys dentata is found from eastern India (and possibly eastern Nepal) southward through Myanmar, Thailand, and peninsular Malaysia, through Sumatra, Java, and Borneo to the Philippines.
Geographic Variation
Considerable color variation occurs within this species. Kou (1989) described a newly discovered Cyclemys from Yunnan Province China, and named it C. tiannanensis, but Das (1991) and Iverson (1992) have placed this turtle in the synonymy of C. dentata, whereas Fritz et al. (1997) thought it synonymous with C. tcheponensis.
Fritz et al. (1996c) recognized four forms within the Cyclemys genus and later designated these to specific rank (Fritz et al., 1997). Taxon D (Fritz et al., 1996c) was simultaneously described by Iverson and McCord (1997b) as Cyclemys atripons and by Fritz et al. (1997) as C. pulchristriata; it is discussed here as Cyclemys n.sp. Cyclemys dentata sensu Fritz et al. (1997), former taxon C (Fritz et al., 1996c), is characterized by a reddish to pinkish, intensely striped head and neck pattern, a yellow plastron with or without narrow black radiations, and cream-colored soft parts. The soft parts of the resurrected Cyclemys oldhamii (Gray, 1863a), former taxon A (Fritz et al., 1996c), are mainly dark colored, and it lacks distinct head and neck stripes; its plastron is dark, and when compared to C. dentata sensu Fritz et al. (1997), adults have a longer interfemoral and shorter interanal seam. Hatchlings and juveniles of both species are similar and can be separated only by the intensity of the head, neck and throat striations (Fritz et al., 1997). C. dentata sensu stricto and C. oldhamii according to Fritz et al. (1997) occur sympatrically from Thailand over Sumatra and Java to Borneo.
Peter Paul van Dijk (pers. comm.) has studied over 100 Thai Cyclemys dentata sensu lato, both living animals as well as museum specimens. From 1991 on, Van Dijk has been studying a population in the Huai Chaang Tai stream, in the Huai Kha Khaeng Wildlife Sanctuary, Uthai Thani Province, western Thailand. He has found much variation within this single population: striated vs. uniformly dark animals, round and broad-shelled vs. elongated and oval-shelled animals, and individuals with domed shells vs. flattened individuals. Van Dijk's impression is that C. oldhamii and C. dentata sensu Fritz et al. (1997) are better considered morphotypes rather than sympatric species occurring in the same habitat. In support of Van Dijk, John B. Iverson (pers. comm.) has told us that striped-headed individuals can be found throughout the range of the genus Cyclemys, suggesting that taxonomy based mainly on head pattern and coloration is problematic. Also, an examination of the morphometric differences between various taxa and populations of Cyclemys by Iverson (in Iverson and McCord, 1997) using discriminate function analysis does not support distinctiveness of C. oldhamii. Variation within this genus is great; in fact, a great continuum of extensive variations occurs across the range, perhaps greater than realized by Fritz et al. (1997). Until a thorough ecological study has been performed that proves the contrary, we feel it is best to concur with Van Dijk and Iverson.
Habitat
This semi-aquatic turtle lives in shallow streams in both the mountains and lowlands.
Natural History
Females mature in 7-10 years (Das, 1995). The nest cavity may be 13-18 cm deep, and 4-5 clutches may be laid each year (Das, 1991). A typical clutch consists of 2-4 elongated, white eggs measuring about 55-57 x 30-35 mm (Smith, 1931; Ewert, 1979; Das, 1991). The female's plastron becomes slightly kinetic to allow these large eggs to be laid. Twelve hatchlings measured by Ewert (1979) had an average carapace length of 56.2 mm.
Cyclemys dentata is omnivorous, and feeds on both animals and plants. It is gentle and lively, and does well in captivity.
IUCN Red List Status (1996)
Not listed.