Magdalena River turtle
This medium-sized Podocnemis reaches a carapace length of 46.3 cm. Its oval adult carapace is flattened, usually keelless, lacks a cervical indentation, and has a smooth posterior rim; however, the juvenile carapace may bear a faint keel and is posteriorly serrated. In both juveniles and adults all vertebrals are broader than long; the 3rd is usually the broadest, the 1st and 5th are smaller than the other three, and the 5th is posteriorly flared. The carapace is gray to olive brown or pinkish brown and may bear some dark spots. The plastron is much smaller than the carapacial opening. Its anterior lobe is shorter than the posterior lobe and is rounded in front. The posterior lobe is about as broad as the anterior lobe and contains an anal notch. The bridge is broad. The plastral formula usually is: abd >< pect > fem > intergul > an >< gul > hum. The intergular is broader than the gulars are long (Williams, 1954a). Both bridge and plastron are olive gray. A protruding snout and an unnotched, slightly rounded upper jaw are present on the narrow head. Two longitudinal ridges occur on the triturating surface of the maxilla; the premaxillae do not separate the maxillae and do not extend posteriorly to the choanal margin. The incisive foramen lies well within the premaxilla. A small vomer bone may be present. The tympanum is as broad as the orbit. The interparietal scale is broad and heart-shaped; the parietals touch behind it. Subocular scales are present, as also are two chin barbels. The head is gray to olive with a yellowish band extending backward from the orbit dorsal to the tympanum and yellowish to horn-colored jaws. Neck and limbs are gray to olive; three large scales occur on the posterior margin of the hind foot.
The karyotype is 2n = 28; 6 large to medium-sized metacentric and submetacentric, 4 large to medium-sized subtelocentric, 14 small to very small metacentric and submetacentric, and 4 small acrocentric and subtelocentric chromosomes (Rhodin et al., 1978).
Males have longer, thicker tails and more obtusely rounded heads than do the females.
Podocnemis lewyana occurs in the Rio Magdalena drainage in Colombia; it has recently been discovered south of Lake Maracaibo, Venezuela (Pauler and Trebbau, 1995).
Podocnemis lewyana is a riverine species which also enters lagoons, swamps, and flood-plain marshes.
Clutches may contain 15 to 30 eggs. The eggs are ellipsoidal, and one measured 40 x 34 mm (Vanzolini, 1977).
The diet is probably similar to that of Podocnemis unifilis.
IUCN Red List Status (1996)
Endangered (A1bd). The present status of this species requires attention as populations appear to be decimated severely throughout its range, especially in the Rio Magdalena.