(Bell, 1828)
Leopard tortoise
Recognition
The carapace (to 70.5 cm) is domed with abruptly descending (almost vertical) sides and somewhat convex vertebral scutes. There is a prominent cervical indentation, but no cervical scute. Anterior and posterior marginals are only slightly expanded and somewhat upturned. Vertebral 1 is as long as or longer than broad, the rest are broader than long, and the 5th is expanded. Well-defined growth annuli surround the vertebral and pleural areolae; areolae may be raised or flattened. There are usually 11 marginals on each side, and a single, undivided supracaudal which may be downturned between the posterior marginals. Dark brown or black pigment occurs along the growth annuli of each pleural and vertebral surrounding the yellow, tan, brown, reddish-brown, or olive areolae. The seams are usually light colored and black smudges occur on the marginals. These marks often fade with age and old individuals may be almost entirely tan or brown; the young, however, are strikingly marked with the characteristic leopardlike spotted pattern. The plastron is well-developed with a deep anal notch. Its two lobes are about the same length, but the hindlobe is slightly wider. The variable plastral formula is: abd > hum >< fem >< gul >< an > pect; the paired gulars are thickened, but only slightly protruding. The bridge is wide with two axillary scutes (one large, one minute) and a single inguinal which touches the femoral scute. The head is moderate with a nonprotruding snout and a hooked, often tricuspid upper jaw. The large prefrontal scale may be single or divided longitudinally; the frontal scale is usually absent, but may be small and subdivided; other head scales are small. The head is uniformly yellow or tan. Limbs and tail are also yellow to brown. The anterior surface of each forelimb is covered with three or four longitudinal rows of large, irregularly shaped, nonoverlapping (or rarely overlapping) scales. Two or more large conical tubercles occur on the hindside of each thigh (these are much smaller than those of G. sulcata), but the tail lacks a large terminal scale.
The leopard tortoise has a karyotype with 52 chromosomes (Dowler and Bickham, 1982; Bickham and Carr, 1983).
The sexes are hard to differentiate, but Loveridge and Williams (1957) found that males had longer, thicker tails and the posterior third of their plastra slightly concave while that of the female is flat. Males also tend to be more elongated with narrower shells that females.
Distribution
Geochelone pardalis is restricted to Africa where it ranges from southern Sudan and Ethiopia southward through eastern Africa to South Africa and westward to southern Angola and Namibia.
Geographic Variation
Formerly two subspecies were recognized—Geochelone pardalis pardalis (Bell, 1828) with a flat-topped carapace, and G. p. babcocki (Loveridge, 1935) with a high, domed or convex carapace—but these forms have been discounted in recent literature (Boycott and Bourquin, 1988; Patterson, 1991; Baard, 1994; Lambert, 1995). Furthermore, Pritchard's (1979) comment that G. pardalis from the highlands of the Graaff-Reinet area of South Africa are more distinctly marked and larger than those from surrounding lowland populations is incorrect (William R. Branch, pers. comm.).
Variation does occur, however; Lambert (1995) reported that leopard tortoises from Somaliland tend to be larger than tortoises elsewhere in Africa. He (1996b) also reported considerable variation in size of leopard tortoises along a north-south gradient from the equator to Cape Province, South Africa, with the largest individuals occurring in the south.
Habitat
These tortoises shun heavily forested areas, but inhabit savannahs, plains, and kopjes with dry woodland, thorn scrub, and grasslands from sea level to over 2900 m (Geochelone pardalis biotope).
Natural History
During the mating period both males and, to a lesser degree, females become aggressive, butting and ramming would-be competitors for their mates. During courtship, the male trails the female, often for some distance, and may butt her to immobilize her. When finally mounted, he extends his neck and utters a gruntlike bellow.
Nesting occurs from May until October, depending on location and latitude. The female digs a flask-shaped hole about 100-300 mm deep, and up to 5-7 clutches of 5-30 eggs may be laid each season (the internesting period is usually about three weeks). The white eggs are spherical (36-44 x 40-52 mm) with brittle shells. Incubation may take over a year. Hatchlings are brightly patterned with round, flattened, serrated carapaces (45-55 mm).
Geochelone pardalis feeds on a variety of wild plants, fungi, grasses, and fallen fruits: crussulas, spekboom, thistles, and the introduced prickly pear. It does almost all of its foraging at ground level. According to Rall and Fairall (1993), during dry years it selects plants to eat according to their availability, grass is eaten as are also succulent plants. More ephemerals are consumed during wet years, but grass is still eaten. Of the 70 species of plants occurring in Rall and Fairall's study habitat, the tortoise only ate 38, ranging from cacti to grasses to succulents. Thirty-four different plants were taken during the dry years; those of highest consumption were Hermannia quartiniana (15.2% occurrence in scats) and Eragrostis lemanniana (13.2%), all other plant species were used by less than 10% of the tortoises. In contrast, only 18 species formed the diet during wet years, with Cynodon dactylon occurring in 16.2% of scats, Schmidtia kalahariensis in 15.7%, and Eragrostis lehmanniana in 14.7%.
To escape the heat of the day, they push into thick bush; bushes and thickets, as well as felled trees, are also used for refuge (Hailey and Coulson, 1995). South African leopard tortoises are inactive during the cold, dry months of May-August (Rall and Fairall, 1993).
IUCN Red List Status (1996)
Not listed. Declines in the numbers of wild leopard tortoises have been caused by collecting for the pet trade. Between 1987-1991, G. pardalis accounted for 76% of the tortoises of various species exported for the pet trade from Africa between 1987-1991 (Kabigumila, 1996).