(Gray, 1834, in Gray, 1830-1835)
Three-striped roofed turtle
Recognition
This is a large species of Kachuga, reaching a carapace length of 48 cm. Its elliptical carapace is widest behind the middle, depressed, and has a smooth posterior rim. A medial keel is present, but reduced to only a posterior projection on the 2nd and 3rd vertebrals in adults. Vertebral 1 is broader than long. The 2nd is broader than long in juveniles but lengthens to become longer than wide in adults. It also becomes more narrowly pointed posteriorly with its posterior margin fitting into the emargination of the 3rd vertebral. Vertebral 3 is broader than long and is shorter than either the 2nd or 4th. As in other Kachuga species, vertebral 4 is longer than broad and the 5th broader than long. The carapace is olive brown with a dark-brown or black medial stripe along the keel and two indistinct dark lateral stripes. The plastron is long and narrow; both the anterior and posterior lobes are shorter than the broad bridge. There is a posterior plastral notch. The humero-pectoral seam is transverse, and joins the plastral midseam at a right angle. The plastral formula is: abd > fem > pect > hum > an >< gul. On the bridge, the inguinal scute is larger than the axillary. Plastron and bridge are yellow; a brownish red blotch occurs on each scute in juveniles. The head is moderate in size with a projecting pointed snout and an upper jaw with a shallow notch bordered on each side by a toothlike projection. Lateral jaw rims are serrated. The skin on the back of the head is divided into scales. The head is olive to brown with a yellow stripe on each side of the head extending backward from the nostril over the orbit and tympanum to the neck. The jaws may also be lighter in color. Neck and limbs are olive or yellowish brown. Enlarged transverse scales are present on the limbs.
The karyotype consists of 52 chromosomes (Bickham and Carr, 1983).
The males are much shorter than the females, not exceeding 26 cm (Smith, 1931), and have long, thick tails.
Distribution
Kachuga dhongoka occurs in Nepal, Bangladesh, and northeastern India in the Ganges and Brahmaputra drainages.
Habitat
This apparently is a turtle of large, deep rivers.
Natural History
Nesting takes place on sandbanks in March and April (Chaudhuri, 1912; Moll, 1986; Das, 1991, 1995). Nest cavities are typically 18-27 cm deep. A normal clutch comprises 16-35 white, oval, elongated (46.0-66.2 x 32.0-41.2 mm) eggs (Rao and Singh, 1987; Moll, 1986; Das, 1995). Egg shells can be either hard or flexible (Das, 1991). The young hatch in May or June (Chaudhuri, 1912).
Kachuga dhongoka is largely herbivorous in captivity, eating a variety of fruits and vegetables (Das, 1995), but wild turtles are known to eat snails (Moll, 1986).
IUCN Red List Status (1996)
Lower risk: near threatened.