Mantidactylus undetermined

Grosjean, Stéphane, STRAUss, Axel, Glos, Julian, Randrianiaina, Roger-Daniel, Ohler, Annemarie & Vences, Miguel, 2011, Morphological and ecological uniformity in the funnel-mouthed tadpoles of Malagasy litter frogs, subgenus Chonomantis, Zoological Journal of the Linnean Society 162 (1), pp. 149-183 : 171-172

MANTIDACTYLUS SP. 13

This is an undescribed species, in its adult stage morphologically close to M. charlotteae (see Glaw & Vences, 2007), that was named Mantidactylus sp. 13 by Vieites et al. (2009). Its tadpoles have no obvious diagnostic characters compared to those of other species of Chonomantis , except for some subtle details of uncertain diagnostic value, and except for M. aerumnalis and M. sp. 59, which can be distinguished, respectively, by their coloration and by the presence of rudimentary keratodonts (see accounts on these species for details).

The description of external morphology of the tadpoles of M. sp. 13 is based on the DNA voucher specimen at stage 26, ZSM 70/2008 (field number ZCMV 4934, GenBank accession number GU808476 ) from a stream at a site locally named Tsitolaka near the village of Ambohitsara, located east of Ranomafana National Park (TL 29.8 mm, BL 7.7 mm).

External morphology: In profile, snout truncate. Eyes directed dorsolaterally. Pineal ocellus present, lying between eyes, at a level situated between sclera and anterior margin of eye. Nares positioned almost dorsally, RN 50% of NP, NN 71% of PP. Spiracle entirely attached to body wall, orientated posterodorsally, SS 51% of BL; spiracular opening not observed, just below apex of caudal myotomes. Tail musculature, TMH 75% of BH and 69% of MTH, TMW 59% of BW, proximal third parallel then gradually tapering, almost reaching tail tip. Tail fins, LF 23% of MTH, SU 94% of BL, upper fin increasing very slowly in first third then abruptly, and convex for two distal thirds, lower fin following caudal muscle; TAL 278% of BL, MTH 108% of BH. Lateral line organs present on snout, above eyes, on flanks and at interface caudal muscle/upper fin, not observed on apex of caudal myotomes.

Oral disc, ODW 41% of BL and 64% of BW. Upper labium with only left lateral extension, right one being missing (present on other specimens of the series). The round structure on midline just behind median notch of same size as other papillae; present part of upper labium bearing a dorsoventrally orientated ridge. Jaw sheaths white with dark serrations; upper jaw sheath wide and shallow, a flattened arch with a median convexity.

Coloration in preservative: Back and upper part of flanks light brown. Lower part of flanks grey in abdominal region, caused by dots on underlying tissues, anterior part translucent grey with some brown dots contained in skin. Ventral side transparent with internal organs visible through skin, some rare small brown dots on throat and chest. Caudal muscle with very numerous brown grey dots, densely arranged leaving only very small beige areas on apex of myotomes anteriorly and on lower part of caudal muscle, these dots forming blotches. Fins translucent grey with some brown dots irregularly arranged having a tendency to cluster more numerous on upper fin. Umbelliform oral disc translucent with very rare grey dots.