Mantidactylus melanopleura, (MOCQUARD, 1901)

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 : 167-168

MANTIDACTYLUS MELANOPLEURA ( MOCQUARD, 1901)

The tadpoles of M. melanopleura 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. melanopleura is based on the DNA voucher specimen in stage 26, ZSM 1318/2007 (field number T0099, Genbank accession number GU975438 ) from Sakaroa, Ranomafana National Park, southern central east of Madagascar (TL 28.1 mm, BL 8.21 mm). A second specimen in stage 25, ZSM 458/2004 (field number FGMV 2002.1972) from An’Ala in central eastern Madagascar, was used for the description of the tail, deformed in the specimen of description (TL 21.6 mm, BL 5.78 mm). Buccopharyngeal features are described based on another DNA voucher in stage 38, ZSM 461/2004 (field number FGMV 2002.1998) from An’Ala.

External morphology: BW 106% of BH ( Fig. 1 ), snout vertical in profile. Eyes, ED 14% of BL, very slightly bulging, barely visible in ventral view. Pineal ocellus at level of anterior margin of eyes. Nares positioned almost dorsally, aperture directed anterolaterally and horizontally, RN 59% of NP, NN 69% of PP. Spiracle moderately sized, opening on mediolateral line, the remaining part of tube below, orientated slightly more posteriorly than strictly posterodorsally, SS 52% of BL; spiracular opening elliptical (pressed against body wall as a result of the fixation), direction of opening not established because of relative shrinkage of specimen, situated on a plane going between hindlimb insertion and apex of myotomes of caudal muscle. Tail musculature, TMH 56% of BH and 61% of MTH, TMW 47% of BW, the proximal third parallel then gradually tapering. Upper fin moderately shallow (almost non-existent in proximal third of upper fin), UF 28% of MTH, SU 100% of BL, beginning abruptly then slightly convex, lower fin shallow, LF 26% of MTH; TAL 263% of BL, its point of maximum height located just before halfway, MTH 93% of BH, tail tip roughly rounded. Anal tube moderately short, directed posteroventrally, proximal half linked to ventral tail fin, distal half free. Lateral line organs present on snout and around eyes dorsally.

Oral disc ( Fig. 2 ) ODW 36% of BL and 57% of BW. The large and round structure on midline of lower labium medium sized relative to other species.

Coloration in preservative: Anterior third of upper side light brown with numerous brown dots on snout, spots more rare behind snout, posterior two thirds transparent with a few brown dots, extension of caudal muscle on back beige. Flanks transparent, internal organs visible through skin, a few brown dots. Ventral side transparent, almost unpatterned at level of abdomen, with rather numerous brown dots on throat and thorax. Caudal muscle beige with numerous brown spots forming a network of dense and numerous spots. Fins translucent with brown spots at interface fins/caudal muscle on anterior half; brown spots on fins between half and three quarters of length of tail, especially on upper fin; a few in distal quarter.

Figures

Figure 1. Lateral and dorsal views of tadpoles of Mantidactylus belonging to the subgenus Chonomantis. Mantidactylus albofrenatus, specimen in stage 26 from the batch ZSM 420/2004. Mantidactylus brevipalmatus, specimen ZMA 7078 in stage 28. Mantidactylus delormei, specimen ZSM 440/2004 in stage 40 (coloration of specimen largely faded and therefore only outline drawn). Mantidactylus melanopleura, specimen ZSM 1318/2007 in stage 26. Mantidactylus opiparis, a specimen from the batch ZSM 416/2004 in stage 25. Mantidactylus zipperi, specimen ZSM 1825/2007 in stage 35. Mantidactylus sp. 59, specimen ZSM 707/2007 in stage 27. Scale bars = 10 mm.

Figure 2. Oral discs of tadpoles of Mantidactylus belonging to the subgenus Chonomantis. Mantidactylus albofrenatus, specimen in stage 26 from the batch ZSM 420/ 2004. Mantidactylus brevipalmatus, specimen ZMA 7080 in stage 27. Mantidactylus delormei, specimen ZSM 440/ 2004 in stage 40. Mantidactylus melanopleura, specimen ZSM 415/2004 in stage 25. Mantidactylus opiparis, specimen from the batch ZSM 416/2004 in stage 25. Mantidactylus zipperi, specimen ZSM 1821/2007 in stage 39. Mantidactylus sp. 59, specimen ZSM 707/2007 in stage 27. Note that the oral disc of M. sp. 59 is drawn in frontal view (all other drawings in dorsal view), and that it contains a row with a low number of keratodont-like structures. Scale bars = 1 mm.