Hylodes meridionalis (Mertens, 1927)

Weber, Luiz Norberto & Caramaschi, Ulisses, 2013, A survey of the internal oral morphology in larvae of the genus Hylodes Fitzinger, 1826 (Amphibia, Anura, Hylodidae), Zootaxa 3635 (5), pp. 557-568 : 562

Hylodes meridionalis (Mertens, 1927)

Material: one specimen (stage 26).

Ventral aspect ( Fig. 5 A): Buccal floor triangular, wider than long; two pairs of infralabial papillae present, apart from one another; the outer pair has a complex structure and is longer than wide, with six finger-shaped projections of irregular margin that touch each other; the posterior pair approximately equivalent to one third of the length of the lingual papilla, with irregular apex surface bearing small pustules; two filiform lingual papillae present, placed side by side, tapered; lingual papillae closer to the first papilla of the buccal floor arena than to the infralabial papilla; there are about 25 papillae on each side, enclosing the buccal floor arena and extending from the region near the tongue rudiments to near the ventral velum; papillae directed to the arena center, finger-shaped and curved; arena papillae arranged similar to a U; the bigger papilla of the floor arena is bifurcate, located in the middle portion of the arena; some arena papillae show irregular margin; about three prepocket papillae, small to medium-sized, similar to those from the buccal floor arena; large number of pustules present on the arena surface, more concentrated in its posterior portion; ventral velum with discrete median notch, undulated margin, and about six finger-shaped projections, with medium size, above the glottis.

Dorsal aspect ( Fig. 5 B): Buccal roof triangular, somewhat shaped as the floor; prenarial arena with low crest and shaped as a reversed V, low distinctive in some specimens; reniform choanae, separated and oriented at an angle of 35° in relation to the transverse plane; distance between choanae slightly lower than the width of the median-ridge; diminute and conical pre-choanal papillae, about three per choana; postnarial arena with six, arranged on each side in a separate row, papillae with varied sizes and finger-shaped; largest papillae posterolocated, finger-shaped, with sharp apex, irregular antero-margin and directed to the center; cluster of papillae in postnarial arena forming an inverted V; presence of a small papilla ahead of the median ridge, not covered by it; complex lateral-ridge papillae, hand-shaped with eight ramifications of anterior margin finely serrate and directed to the center, the first ramification less developed than the others; the median ridge triangular-shaped with irregular margin; buccal roof arena bordered by 14 papillae on each side, finger-shaped, tapered, and with anterior margin aliasing, directed up and to the arena center; some of them with two or three little ramifications on the apex; absence of large bifurcate papilla in the arena; arena papillae forming an approximate U or V design; pustules are present and evenly distributed in arena surface; distinct row with about nine lateral papillae on the roof arena; not distinct glandular area; dorsal velum medially interrupted, having about eight uniform projections of small size.

Figures

FIGURE 5. (A) Floor and (B) roof of the buccal surface in a Hylodes meridionalis tadpoles at stage 26. Scale = 1 mm.