The tadpole of the toadlet Scaphiophryne marmorata from Madagascar

Abstract

The genus Scaphiophryne Boulenger comprises eight species of microhylid toadlets (Vences et al. 2003; Glos et al. 2005), all of which are endemic to Madagascar. They are characterized by a unique larval morphology, intermediate between Orton's (1953) types II and IV (Blommers-Schlösser 1975; Wassersug 1984). Recently, Grosjean et al. (2007) provided a comparative study of larval morphology of the genus, and found evidence for two morphological subgroups based on larval characters. Tadpoles remained unknown for only two species, Scaphiophryne boribory Vences, Raxworthy, Nussbaum & Glaw, and S. marmorata Boulenger.
Three tadpoles of S. marmorata were collected by M. Vences, H. Kurrer and L. du Preez on 7 February 2006 close to Andasibe (18°56′S/48°25′E, 915 m a.s.l.), in a large temporary pond of about 15 m diameter and maximum water depth of 1 m, at the edge of rainforest. They were found syntopically with larvae of Paradoxophyla palmata and Boophis pauliani. Identity of one of these specimens (ZSM 554/2008) was verified by DNA barcoding; the sequence of a fragment of the 16S rRNA gene has the Genbank accession number EU717878 and was identical to a sequence of an adult specimen from the same locality (accession AY834191). Vouchers were deposited in the Zoologische Staatssammlung München, Germany (ZSM). We here provide a detailed description of these larvae, based mainly on one specimen at stage 39, ZSM 555/2008 (field number ZCMV 3602). Measurements were taken using a stereo microscope (Zeiss Stereo Discovery) using landmarks as in Grosjean et al. (2007).