A New Amber-embedded Sphaerodactyl Gecko from Hispaniola, with Comments on Morphological Synapomorphies of the Sphaerodactylidae

A new species of Sphaerodactylus (Squamata: Gekkota: Sphaerodactylidae) is described from an amber inclusion from the late Early Miocene or early Middle Miocene (15 to 20 million years ago) of the Dominican Republic. Unlike earlier amber-embedded specimens assigned to this genus, the new specimen is largely skeletal, with some integument remaining. A combination of 258 (of 674) osteological and external characters could be scored for the new species in a cladistic analysis of 21 gekkotan species, including representatives of all sphaerodactylid genera. The most parsimonious trees obtained confirm the placement of the amber gecko within the genus Sphaerodactylus and a comparison with extant Hispaniolan and Puerto Rican congeners suggests phenetic similarity both with members of S. difficilis complex and the S. shrevei species group. Character mapping on the basis of the phylogenetic analysis permits the preliminary identification of morphological characters diagnostic of the Sphaerodactylidae, Sphaerodactylini, and Sphaerodactylus. Osteological features of the new species are discussed in the broader context of sphaerodactyl, sphaerodactylid, and gekkotan variation. Extant Hispaniolan Sphaerodactylus display significant ecomorphological variation and it is likely that the many known, though not yet described, amber-embedded specimens will eventually reveal similar patterns in their Miocene congeners.