Carr and Marchand, 1942
Barbour's map turtle
Recognition
This broad-headed turtle (to 32 cm) has a black-tipped, tuberculate medial keel. The 2nd and 3rd vertebrals bear slightly concave tubercles; the 1st and 4th bear a low spine or ridge. Vertebrals are broader than long; the 1st is smallest, the 5th expanded. The posterior rim of the carapace is strongly serrated. The carapace is olive to dark brown; pleurals and marginals have a pattern of pale yellow to white oval markings, which open posteriorly (these are often lost in large females). Undersides of the marginals are marked at the posterior seam with a dark, semicircular blotch. The deep plastron is greenish yellow to cream colored, with a narrow black border along the posterior margin of each scute except the anals; the border tends to fade with age. Well-developed spinelike projections are present on the pectoral and abdominal scutes, and the hindlobe is posteriorly notched. The plastral formula is: abd > an > fem > gul >< pect > hum. The head is broad in females, but narrower in males. It has a nonprojecting snout, and neither a hook nor notch on the upper jaw. The head is dark brown or black with three broad, light areas, which are interconnected: one on the snout and two behind the eyes. The 12-14 stripes on the nape of the neck are connected with the postocular blotches. The chin exhibits a curved, light bar, which often parallels the curve of the jaw. Other skin is brown or black with light stripes.
Killebrew (1977a) reported a diploid number of 50 (26 macrochromosomes—16 metacentric, 6 submetacentric, and 4 telocentric—and 24 microchromosomes).
Adult males are 9-13 cm in carapace length, adult females 17-27 cm. Males have long, thick tails, with the vent posterior to the carapacial margin. In males the head is small and narrow; in females it is large and short-snouted.
Distribution
Graptemys barbouri occurs in the Gulf coastal streams of the Apalachicola River system in the Florida Panhandle (including the Chipola) and adjacent Georgia. It apparently occurs only below the fall line.
Habitat
Graptemys barbouri lives in clear, limestone-bottomed streams with abundant snags and fallen trees.
Natural History
Males are sexually mature at a plastron length of about 6.9 cm an age of four years (Cagle, 1952b). The smallest mature female examined by Cagle (1952b) had a plastron length of 17.6 cm. Females probably require 15-20 years to reach maturity (Sanderson, 1974). During courtship the male approaches the female with his neck extended. He swims around her until they are face to face, and after nose contact he strokes her head with the inner side of his forelegs (Wahlquist, 1970).
Nesting probably occurs in June, but has not been described. Nests found by Wahlquist and Folkerts (1973) were 8-16 cm deep in moist sand. Clutches found by them consisted of eight and nine eggs (38.3-41 x 27.6-30.8 mm). The eggs were ellipsoidal and dull white with flexible shells. Hatchlings emerge in late August and September with 35-38-mm carapaces.
Female foods consist of mussels and snails; males eat smaller snails, insects, crayfish, and fish.
IUCN Red List Status (1996)
Lower risk: near threatened. This turtle is rare and threatened by pollution of its waterways and by collection for the pet trade.