A Revision of the Dwarf Zonosurus Boulenger (Reptilia: Squamata: Cordylidae) from Madagascar, including Descriptions of Three New Species

Abstract

Surveys in Madagascar led to the discovery of three new species of dwarf Zonosaurus. One is endemic to limestone karst formations in the north, the second is endemic to limestone karst formations in the west, and the third is endemic to the low elevation humid forests in extreme southeaster Madagascar. The two new karst-inhibiting species are the first species of Zonosaurus known to be confined to rocky habitats. The northern karst-inhabiting species and Zonosaurus subunicolor have fragile skin. This seems to be an antpreditor mechanism, and within the Cordylidae is uniquely evolved. The holotype of Zonosaurus aeneus is redescribed, and data are presented for Z. brygooi and Z. subunicolor, based on our recently collected material. A key is provided for all seven dwarf species. Biogeographic patterns show a clear predominance for allopatry, with all species are restricted to primary forests, or forest edge. The new species from southeastern Madagascar is of greatest conservation concern, and further strengthens the importance of the Andohahela Reserve, where it is known to occur.