Multi-gene phylogeny of Madagascar's plated lizards, Zonosaurus and Tracheloptychus (Squamata: Gerrhosauridae)

Abstract

We analyzed the phylogenetic relationships of the Malagasy plated lizards in the family Gerrhosauridae based on DNA sequence fragments of four mitochondrial and five nuclear genes. Various clades were strongly supported by the concatenated data set and also recovered by separate analyses of mtDNA and nucDNA. In particular, two clades here named the Z. rufipes group (containing Z. bemaraha , Z. brygooi , Z. rufipes , Z. subunicolor , Z. tsingy and an undescribed candidate species from northern Madagascar) and the Z. ornatus group (containing Z. anelanelany , Z. laticaudatus , Z. karsteni , Z. ornatus , Z. quadrilineaus, and Z. trilineatus) were resolved with strong support. A third clade named the Z. madagascariensis group contains Z. madagascariensis with a nested Z. haraldmeieri; the status of that species requires further investigation. Tentatively we also include Z. aeneus in this species group although its phylogenetic relationships were poorly resolved. A fourth clade with less support included Z. boettgeri and Z. maximus. The phylogenetic position of the genus Tracheloptychus remains uncertain: whereas in the species tree it was recovered as the sister group to Zonosaurus, other methods indicated that it was nested within Zonosaurus, albeit alternative topologies were rejected with only marginal statistical support.

Keywords: Biogeography; Madagascar; Molecular systematics; Tracheloptychus; Zonosaurus.