Cuora amboinensis

(Daudin, 1802)
Malayan box turtle

Adults have a high-arched carapace (to 21.6 cm) with or without a medial keel; the juvenile carapace is depressed and bears three prominent keels. The 1st vertebral is wider anteriorly than posteriorly, the 2nd and 5th are longer than broad, and the 3rd and 4th are usually broader than long. Posterior marginals are slightly flared, but not serrated, and the carapace also lacks a posterior notch. The carapace is uniformly dark olive or black in color. The large plastron can completely cover the carapacial openings. The posterior lobe is rounded, and usually contains no medial anal notch, or only a slight one. The plastral formula is: abd >< an > pect > gul > fem > hum. Axillary and inguinal scutes are very small or absent. The plastron is yellow to light brown, and there is a large dark-brown or black spot toward the outside of each scute. Undersides of the marginals are yellow, and each has a black spot along its border. The head is small to medium with a protruding snout and a slightly hooked upper jaw; it is olive to dark brown dorsally, becoming black laterally, and yellow to olive posteriorly. On each side, a black-bordered yellow stripe runs anteriorly from the neck passing above the orbit to the tip of the snout above the nostrils, where it meets its counterpart from the other side. Two other pairs of yellow stripes are also present on each side of the head. The first passes posteriorly from the nostril through the orbit and tympanum to the side of the neck. The second passes from below the nostril along the upper jaw backward to the neck. Lower jaw and chin are yellow, limbs are olive to black, and the anterior surfaces of the forelimbs are covered with enlarged horizontal scales.
The karyotype is 2n = 52; 28 macrochromosomes (18 metacentric or submetacentric and 10 telocentric or subtelocentric and 24 microchromosomes (Carr and Bickham, 1986); Kiester and Childress (in Gorman, 1973) erroneously reported the karyotype to be 2n = 50.
Males have slightly concave plastra and longer, thicker tails. Females are somewhat larger than males.

Cuora amboinensis occurs from the Nicobar Islands, Bangladesh (Khan, 1982), and Assam (Moll and Vijaya, 1986), south through Myanmar, Thailand, Cambodia, Vietnam, and Malaysia, and east to Sulawesi, Amboina (the type locality) and the Philippines.

Geographic Variation
Three subspecies are currently recognized, but additional variation has been reported (Hans-Dieter Philippen, pers. comm.), and it is likely that more subspecies will be described. Cuora amboinensis amboinensis (Daudin, 1802), the East Indian box turtle, occurs in the Moluccas, Sulawesi and the Philippines. It has a flattened carapace with flared marginals, and a plastral pattern consisting of a dark blotch on each scute and often faded dark pigment medially. C. a. kamaroma Rummler and Fritz (1991), the Southeast Asian box turtle, ranges from India and Bangladesh and the Nicobar Islands through southeastern Asia to the Malay Peninsula; it also occurs on Borneo and the Philippines. It has a highly domed carapace with unflared marginals, and a yellow plastron with dark blotches that are generally small, reduced in number, and relegated to the outer edges of the scutes. The West Indonesian box turtle C. a. couro (Schweigger, 1812) occurs on Sumatra, Java and nearby islands in western Indonesia. Rummler and Fritz (1991) reported it is intermediate in characters between the other two subspecies: carapace only moderately domed with or without flared marginals, and with a plastron pattern of dark blotches that are smaller than those of C. a. amboinensis.

This turtle inhabits lowland water bodies with soft bottoms and slow currents, such as marshes, swamps, ponds, pools in streams, and manmade flooded rice paddies. Although highly aquatic, it is often found on land far from water. Taylor (1920) reported that the juveniles are entirely aquatic.

Natural History
Hofstra (1994) observed behavior of two females which he interpreted as courtship behavior: the animals face each other and with outstretched necks they move their heads in the shape of an infinity symbol. Inskeep (1984a) reported the male is aggressive during courtship, biting the neck of the female if she tries to struggle free, leaving large sores on her neck.
Two to four clutches, usually of only two (1-5) eggs, are laid between April and the end of June. In captivity, nesting takes place between February and June (Inskeep, 1984a, b; Saxena, 1994). The brittle-shelled, white eggs are elongated and measure 40-52 x 26-34 mm (Smith, 1931; Inskeep, 1984a). The tricarinate hatchlings are about 38-48 mm in carapace length.
In the wild, Cuora amboinensis is decidedly herbivorous, but captives soon learn to take various animal foods.

IUCN Red List Status (1996)
Lower risk: near threatened.