Rhombophryne vaventy Scherz, Ruthensteiner, Vences & Glaw, 2014, sp. nov.

Rhombophryne vaventy sp. nov. (Figs. 1–3) Rhombophryne serratopalpebrosa —Glaw & Vences 2007: pp. 118–119, Fig. 3 a. (depicts the paratype, FGZC 2842) Rhombophryne sp. 4 — Wollenberg et al. 2008 Rhombophryne sp. 6 — Vieites et al. 2009: Suppl. Material Rhombophryne sp. aff. serratopalpebrosa —D’Cruze et al. 2010 Rhombophryne sp. Ca 6 Marojejy—Perl et al. 2014: Suppl. Material Holotype. ZSM 357 / 2005 (FGZC 2876), adult male, collected by F. Glaw, M. Vences, R.D. Randrianiaina on 17 February 2005 at Marojejy National Park, “Camp Simpona”, 14 ° 26.199 'S, 49 ° 44.601 'E, 1326 m above sea level), northeastern Madagascar. Paratype. UADBA uncatalogued (FGZC 2842), probably adult, sex unknown, collected by F. Glaw, M. Vences, R.D. Randrianiaina on 16 February 2005 at Marojejy National Park, “Camp Simpona”, 14 ° 26.199 'S, 49 ° 44.601 'E, 1326 m above sea level), northeastern Madagascar. GenBank Accessions Numbers: KF 611595, EU 341107. Diagnosis. A microhylid frog assigned to the genus Rhombophryne on the basis of molecular data (see discussion below). Currently there are no morphological characters to distinguish between Rhombophryne and Plethodontohyla (Andreone et al. 2005; Wollenberg et al. 2008; Glaw et al. 2010). This species differs from all other Rhombophryne species and from all Plethodontohyla species by the combination of the following characters: large size, rough and tubercular dorsal skin, smooth ventral skin, fingers and toes without enlarged terminal discs, tibiotarsal articulation reaching beyond snout tip, second finger shorter than fourth, fifth toe shorter than third toe, a series of four soft superciliary spines, anterior-most two being most distinct, absence of dorsolateral folds, dark colouration beneath chin fading to lighter posteriorly, dorsal brown colouration with distinct black spots arranged almost symmetrically, a series of faint but distinct crossbands on the legs, stepped columellar footplates (Fig. 2 e), curved prevomers and vomerine teeth (Fig. 2 d), and nasals with a posterior but no anterior lateral process (Fig. 3 c). It differs from all other sequenced Malagasy microhylid frogs by a pairwise genetic divergence in its 16 S rDNA sequence of ≥ 6.6 %, being most closely related to R. sp. ‘Ambolokopatrika’ as discussed above (Vieites et al. 2009). Additionally, R. vaventy may be distinguished from its congeners by the following characteristics: from R. mangabensis by larger size (53 mm vs. 20–24 mm), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum), and the presence of four superciliary spines (vs. absence); from R. alluaudi by tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum), and the presence of four superciliary spines (vs. absence); from R. testudo by larger size (53 mm vs. 33–45 mm), absence of barbels on the lower lip (vs. presence), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum), and the presence of four superciliary spines (vs. absence); from R. coudreaui by larger size (53 mm vs. 28 mm), absence of webbing between digits (vs. traces of webbing), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum), and the presence of four superciliary spines (vs. absence); from R. guentherpetersi by larger size (53 mm vs. 32–35 mm), absence of porous glandular formation in the latero-dorsal region (vs. presence), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the eye), and the presence of four superciliary spines (vs. absence); from R. laevipes by larger size (53 mm vs. 45–47 mm), granular and tubercular dorsal skin (vs. smooth), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the eye or nostril), and the presence of four superciliary spines (vs. absence); from R. minuta by larger size (53 mm vs. 16–22 mm), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the eye), and the presence of four superciliary spines (vs. absence); from R. matavy by larger size (53 mm vs. 39–49 mm), tibiotarsal articulation reaching beyond the snout tip (vs. not reaching the insertion of the arms), and the presence of four superciliary spines (vs. absence); from R. coronata by much larger size (male SVL 53 mm vs. 21–23 mm), coarsely granular and tubercular dorsal skin (vs. slightly granular), presence of a distinct supratympanic fold (vs. indistinct supratympanic fold), smaller relative tympanum diameter (TDH/ED 41 % vs. 51 %), tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum), and longer relative tibia length (TIBL /SVL 56 % vs. 39–41 %). Rhombophryne vaventy may be distinguished from R. serratopalpebrosa by larger size (53 mm vs. 28 mm), distinct supratympanic fold not extending beyond the anterior edge of the tympanum (vs. strong, almost straight supratympanic fold extending to the supraocular region), presence of almost symmetrical dark dorsal spots (vs. absence), and much smaller relative tympanum size (TDH/ED 41 % vs. 78 %). Furthermore, the following osteological differences were noticed (Figs. 2 and 3): shape of the columellar footplate (stepped vs. domed), relative length of the prepollex (61 % vs. 28 % of first metacarpal), relative extension of the ilium (reaching the eighth presacral vertebra vs. reaching the seventh presacral vertebra), lateral processes of the nasal bone (just posterior vs. anterior and posterior), postchoanal prevomerine palate (curved vs. straight), the size order of the breadths of the vertebrae, measured from the tips of the transverse processes (L 3 <L 2 <L 4 <L 1 <T 1 <S <T 3 <T 2 vs. L 2 <L 3 <L 1 <L 4 <T 3 <T 1 <S <T 2; S = Sacrum), shape of the posterior vertebral articulations (slender vs. rounded), ossification of the sternum (present vs. absent), and the angle of the medial process of the pterygoid. However, due to the extremely low number of specimens available (one male of R. vaventy and one female of R. serratopalpebrosa), we cannot exclude that some of these apparently diagnostic features are due to sexual dimorphism, individual variation, or differences in resolution of the CT scans. Rhombophryne vaventy may be distinguished from all species of Plethodontohyla by the presence of superciliary spines (vs. absence), and from all Plethodontohyla except P. t uberata by its roughly tubercular skin (vs. smooth to granular skin). Additionally, it may be distinguished from P. notosticta, P. guentheri, P. mihanika, and P. inguinalis by the lack of enlarged terminal discs on its digits (vs. presence) and the lack of a sharp border between the dorsal and lateral colouration (vs. presence); from P. t ub e r a t a by larger size (53 mm vs. 35–45 mm), tibiotarsal articulation reaching beyond the snout tip (vs. the insertion of the arms); from P. ocellata by absence of large black spots bordered with white in the inguinal region (vs. presence), and tibiotarsal articulation reaching beyond the snout tip (vs. reaching the tympanum); from P. bipunctata by larger size (53 mm vs. 25–32 mm), and tibiotarsal articulation reaching beyond the snout tip (vs. reaching the insertion of the arm, the tympanum, or the eye); and from P. brevipes by larger size (53 mm vs. 36 mm), and tibiotarsal articulation reaching beyond the snout tip (vs. reaching the insertion of the arms). Description of the holotype. Specimen in a very good state of preservation. A piece of muscle was taken from the right thigh as a tissue sample for genetic analyses. An incision was made in the right flank to check the sex and examine the contents of the intestines. Body robust. Head wider than long. Pupil very small and roundish. Snout rounded in dorsal and lateral view. Canthus rostralis slightly concave. Loreal region slightly concave. Nostrils closer to tip of snout than to eyes; directed laterally; not protuberant. Eye-nostril distance smaller than the internarial distance. Tympanum distinct, rounded, 41 % of eye diameter. A series of four short but distinct soft dermal spines present above each eye, not equally spaced; anterior two most distinct, the third almost imperceptible. Distinct supratympanic fold, curved over and behind the tympanum, not extending anteriorly beyond the tympanum. Vomerine teeth present, curving posteriorly toward the medial line of the palate. Tongue broad and disc-like, without distinct lobes. Arms stout. Fingers without webbing, relative lengths 1 <2 <4 <3. Fourth finger distinctly longer than second. Finger tips distinct but not enlarged; nuptial pads absent; prepollex not externally visible; inner metacarpal tubercle present; outer metacarpal tubercle absent. Hindlimbs long and muscular; tibiotarsal articulation reaches slightly beyond the snout tip; tibial length 56 % of SVL. Large inner metatarsal tubercle present, outer metatarsal tubercle absent; no webbing between toes; relative toe lengths 1 <2 <5 <3