Additional species of Mabuya Fitzinger (Reptilia : Squamata : Scincidae) from western Madagascar

Two new Species of the lygosomine, scincid genus Mabuya, tentatively assign ed to the aureopunctata-Group, are described from the drier regions of west ern Madagascar. Mabuya tandrefana sp. nov. was found at seven sites ranging from Kirindy Forest northward along the western coastal belt to Baly Bay. It occurs in tsingy, limestone habitats in Bemaraha and Namoroka Reserves a nd on the ground and bases of tree trunks in dry, deciduous forests and in savannah dominated by satrana palms. It is a small- to medium-sized species (adults 50-58 mm SVL) identified by (1) the presence of a rectangular subo cular scale, (2) absence of a bold pattern of white spots on a dark backgro und on the dorsal and lateral surfaces of the head, neck, and anterior half of the body, (3) four supraocular scales and a model number of five (4-6) superciliary scales, (4) dorsum nearly immaculate brown to tan-brown separa ted from a black lateral stripe by a dorsolateral, narrow, light tan stripe , which may be faintly expressed or absent, especially posteriorly, and (5) absence of a ventrolateral, white stripe below the black lateral stripe. M abuya volamenaloha sp. nov. is known from three sites in the deciduous dry forests and tsingy habitats associated with Bemaraha Reserve. It is smaller than M. tandrefana (adults 48-52 mm SVL), with which it is sympatric, and has the same scalation pattern (rectangular subocular, four supraoculars, f ive superciliaries). If: is further identified by having (1) a lateral blac k stripe front behind the eye to just above the forelimb or slightly beyond , below which is a row of large white spots that may be fused or partially fused into a white line extending from below the eye, across the ear, and e nding above the forelimb or further posteriorly on the body, (2) a bright c oppery (in life) dorsal head coloration, and (3) five, dorsal, coppery, lon gitudinal stripes on a black ground color extending from the back of the he ad onto the neck, fading posteriorly and disappearing above the pelvis. These two new forms increase to 14 (possibly 15 if the holotype of M. betsi leana was collected in Madagascar) the number of Mabuya species known for M adagascar, all but one of which are endemic. The discovery during the past five years of eight new skinks of the genus Mabuya in Madagascar, more than doubling the number of species known for that island, dramatically emphasi zes both our poor understanding of the biodiversity of Madagascar and the s tartlingly high number of species endemic to this island.