(Schweigger, 1812)
Mediterranean turtle
Recognition
This is a brown, medium-sized (to 18 cm), semi-aquatic turtle of the western Mediterranean region. Its low, oval carapace is slightly keeled medially (much more strongly in juveniles than in adults), and has a smooth, unserrated marginal border. Cervical and vertebral scutes are usually broader than long. A pair of low lateral keels are present on the pleural scutes of hatchlings but these become lower with age and, at best, are barely visible in adults. The carapace is tan to olive with large, black-bordered, yellow to orange blotches on each scute. A broken medial stripe is usually present, but fades with age, so that older adults may be uniformly tan or olive. The well-developed plastron is notched and somewhat pointed posteriorly. Its formula is: abd > fem > pect > gul > an > hum in males; in females, the pectoral and femoral scutes are reversed. The yellow plastron has a large, central, dark blotch which may contain a yellow median streak. This pattern also fades with age. The yellow bridge is well-developed and has two dark blotches which may join medially. The head is not greatly enlarged; it is olive to grayish tan with a series of yellow stripes which begin on the neck, pass dorsal to the tympanum, and extend to the orbit. Often an incomplete yellow ring encircles the tympanum, and a yellow line extends from the neck to the corner of the mouth and continues along the border of the upper jaw to its tip. A round yellow or orange spot lies between the tympanum and orbit; this may touch the tympanic ring. Neck, limbs, and tail are olive with yellow stripes or vermiculations. The carapace often has infected areas around the scute seams resulting from algae and bacteria invading the soft developing tissues beneath the scutes; this led Schweigger (1812) to apply the trivial name leprosa to this turtle.
The karyotype consists of 52 chromosomes; 28 macrochromosomes (18 metacentric or submetacentric, 19 telocentric or subtelocentric) and 24 microchromosomes (Bickham and Baker, 1976a).
Females grow larger than males, have flat plastra, wider heads, and shorter tails with the vent beneath the carapace. Males are smaller, have concave plastra, narrower heads, and longer, thicker tails with the vent posterior to the carapacial margin.
Distribution
Mauremys leprosa occupies the western end of the Mediterranean region from southwestern France, Spain and Portugal to western Libya, Tunisia, Algeria, Morocco, around northwestern Africa to Senegal, Dahomey, and Niger.
Geographic Variation
Schleich (1996) described six subspecies for Morocco alone. These are mainly separated by differences in shell and soft part coloration, which are present in juveniles and subadults, but are lost in adults. He placed the subspecies in three groups: the "atlantica" -group, with Mauremys leprosa atlantica (north Atlantic coast in the vicinity of Larache), M. l. erhardi (Middle Atlas northeast of Taza), and M. l. wernerkaestlei (Oued Serou, Oued Oum er Rbia, south of Khneifra); the "marokkensis" -group, consisting only of M. l. marokkensis (from south of Marrakech to west of Agadir); and the "saharica" -group, with M. l. saharica (Oued at Goulmime, south of the High Atlas) and M. l. zizi (Oued Ziz, south of Errachidia). Busack and Ernst (1980) noted that juveniles (to 11 cm plastron length) from Tunisia and Libya usually have the dark pigment reduced on the gulars, humerals, and anterior half of the pectoral scutes, while those from Morocco, Algeria, and Spain have extensive dark pigment on these scutes. Also, Mosauer (1934) reported that Tunisian specimens from Gafsa had uniformly brown carapaces, whereas those from Gabes had a distinct pattern of sharply outlined red spots on their pleurals and some red on each marginal. These red marks faded with age.
Until Schleich's study has been expanded with the rest the distribution area, and his study thoroughly has been evaluated, we feel a conservative approach should be applied to the taxonomy of Mauremys leprosa. For the time being, it seems best to treat the Mediterranean turtle as a monotypic species.
Habitat
This turtle lives in almost every type of permanent freshwater habitat within its range: rivers, streams, brooks, ponds, sloughs, marshes, lakes, and the pools of oases. It has been collected in temporary waters such as drainage ditches and latrines, and in brackish waters.
Natural History
Breeding takes place in early spring, March and April, and the usual nesting period encompasses May and June. A wild breeding pair was observed by Ernst on 8-9 March 1976. The 11 cm male trailed the female of the same length, often biting at her flanks and tail. When she was caught, he crawled onto her back, hooked the toes of all four feet under her shell, and held fast. The male then bit the female's gular skin in a bulldoglike grip while manipulating his tail under her to achieve copulation. During this period the totally submerged female was relatively passive with her head withdrawn, although she did crawl about some with the male on top. Mating may also occur on land. Nests are shallow holes, usually in sandy areas or between tree roots.
4-13 elongated (25.8-40.4 x 18.1-34.9 mm) eggs form a clutch (Andreu and Villamor, 1989; Pérez-Quintero, 1989; Da Silva, 1995). The incubation period ranges from 25 days to around 65-75 days, depending on latitude and weather conditions.
Hatchlings are about 32 mm in carapace length and are brighter colored than adults, with a medial and two lateral carapacial keels. Hatchlings are extremely shy and remain hidden among bottom debris.
Adults are fond of basking, but are extremely alert, diving into the water at the least disturbance. When handled they may bite, release bladder water, or emit a malodorous secretion from their inguinal glands.
In the wild their diet consists of fish, adult frogs and tadpoles, insects, aquatic invertebrates, algae and aquatic plants, and carrion. Large adults may be cannibalistic. Food can be swallowed both in or out of the water. The northern populations may hibernate in winter, while those in more southerly, arid situations maybe forced to aestivate in summer.
IUCN Red List Status (1996)
Not listed.