Dendrophryniscus organensis, Carvalho-E-Silva & Mongin & Izecksohn & Carvalho-E-Silva, 2010

Carvalho-E-Silva, Ana Maria Paulino Telles De, Mongin, Marcelle Mantoanelli, Izecksohn, Eugenio & Carvalho-E-Silva, Sergio Potsch De, 2010, A new species of Dendrophryniscus Jiménez-de-la-Espada from the Parque Nacional da Serra dos Órgãos, Teresópolis, State of Rio de Janeiro, Brazil (Amphibia, Anura, Bufonidae), Zootaxa 2632 (1), pp. 46-52 : 48-51

Dendrophryniscus organensis sp. nov.

Etymology: The specific epithet refers to the locality where the species was found, the Parque Nacional da Serra dos Órgãos, in the State of Rio de Janeiro, Brazil.

Holotype ( Fig. 2A–D, Fig. 3A–B): ZUFRJ 9794 , adult female, collected in the Parque Nacional da Serra dos Órgãos (22 o 27’S, 42 o 59’W; about 1050 m a.s.l.), Municipality of Teresópolis , State of Rio de Janeiro, Brazil, by Sergio P. Carvalho-e-Silva, Victor G. D. Orrico, and Leandro Duarte da Cruz, on February 2005.

Paratypes: All collected in the type locality: UNIRIO 2183, adult female, collected by Marcelle M. Mongin and Victor G. D. Orrico, on April 21, 2005; UNIRIO 2406, adult female, collected by Marcelle M. Mongin, Victor G. D. Orrico, and Ana Maria P. T. de Carvalho-e-Silva on April 02, 2006 .

Diagnosis: Dendrophryniscus organensis sp. nov. is characterized by having: 1) rostral angle sharp, distinct; 2) snout acuminate, triangular in dorsal view; 3) snout in ventral view with sub-rostral crests converging anteriorly, with granules irregularly arranged in a triangular area with an anterior vertex; 4) dorsum covered with many scattered small conical granules; 5) dorsal pattern with two mirrored convex stripes in the scapular region and a longitudinal median stripe to the vent region, both dark brown; 6) point of snout, sub-rostral crest, and tips of fingers and of toes reddish orange; 7) dilation of third finger one–third the diameter of the eye; 8) mean SVL in females 23.6 mm (range 23.2–23.8 mm; n = 3); and 9) tibia about 44% of the snout-vent length (Table 1).

Comparisons with other species: Besides the unique dorsal color pattern ( Fig. 2E), Dendrophryniscus organensis is distinguished from D. minutus , D. carvalhoi , and D. stawiarskyi in having a sub-rostral crest converging anteriorly (similarly to D. berthalutzae , D. leucomystax , and D. bokermanni ); the largest finger of the hand is the 3rd (differing from D. bokermanni in which it is the 1st); inner tarsal tubercle elliptical (rounded in D. carvalhoi , D. brevipollicatus , and D. krausae ); inner tarsal tubercle large (tiny in D. carvalhoi , D. berthalutzae , and D. krausae ); the dilation of the third finger is one–third the diameter of the eye, as in D. berthalutzae , and is larger than in D. carvalhoi , D. brevipollicatus , D. stawiarskyi , and D. leucomystax , and smaller than in D. bokermanni and D. minutus .

The largest measurement of the snout-vent length of the females of D. organensis is smaller than that observed in the females of D. brevipolicatus , D. krausae , and D. bokermanni , and larger than in D. minutus . In D. organensis , the ratio of the tibia length to snout-vent length is relatively equal to that in D. carvalhoi , larger than in D. krausae , D. brevipolicatus , and D. stawiarskyi , and smaller than in D. bokermanni , D. leucomystax , and D. minutus . Dendrophryniscus organensis , although larger than D. minutus , has a proportionally smaller tibia ( Table 2).

Holotype description: Female with SVL 23.8 mm, dorsal pattern composed by two mirrored convex stripes “) (” on the scapular region and one dorsal stripe on the middle of the body, extending to the vent region; dorsum covered by many scattered small conical granules; snout ventrally with sub-rostral crests converging anteriorly, with some granules arranged irregularly in a triangular area with the vertex anterior; projection of snout tapering, extending beyond end of mandible; nostril lateral, closer to the end of the snout than to eye; rostral angle pronounced, easily distinguishable, with the snout triangular in dorsal view; loreal region flat, nearly vertical; small reddish protrusion on rostral angle, slightly behind the nostril; eyes wide, prominent, moderately projecting, with diameter approximately equal to the distance from the eyes to the nostril; no external tympanum visible; tongue narrow, entire, oblong, attached by the anterior part; fingers united at the base; first finger very short, fourth finger 1.3 times longer than the second, and third expanded to the base of the last tubercle; few dermal grooves; subarticular tubercles high, rounded; width of dilation of third finger one–third of ocular diameter and corresponding to 1.3 times the width of half the finger; subarticular tubercles on the fingers elevated, rounded, present on third and fourth fingers; tubercles at base of fingers rounded, with some accessory tubercles; external carpal tubercle rounded, prominent; relative finger length 1<2<4<3; tibia equal 46% of the snout-vent; feet with vestiges of the interdigital membrane at the base of the toes; outer metatarsal tubercle rounded, prominent; inner metatarsal tubercle elliptical, flattened; toes with subarticular tubercles rounded, prominent; tubercles at base of toes rounded, raised; supernumerary tubercles absent; relative toes length 1<2<3<5<4; venter cream with black spots and flecks; gular region intensively mottled with black.

Coloration: Dorsal pattern distinct for the genus, with two stripes that arise behind the eyes, continuing in parallel toward the back, diverging and ending abruptly in the middle of the dorsum. At the point where the upper stripes diverge, another stripe arises and follows the vertebral column. In the sacral region there is a stripe perpendicular to the vertebral column on each side, which extends to the legs when in the characteristic position ( Fig. 2E).

In life, the dorsal pattern is dark brown (Vandyke Brown, 121); the dorsum is light brown (Dark Drab, 119B); the tips of fingers and toes, the snout, and the dorsal crest vary from light orange (Spectrum Orange, 17) to dark red (Scarlet, 14); the venter is pale yellow Pale Horn, 92) with dark spots (Vandyke Brown, 121) that are more evident in the gular region ( Fig. 4).

Natural history: The specimens were found in February and April, near the Estrada da Barragem , in the Parque Nacional da Serra dos Órgãos. The three specimens were collected soon after nightfall, under a light rain. Specimen ZUFRJ 9794 was collected on leaf litter; specimen UNIRIO 2183 on a root about 20 cm above the ground, and specimen UNIRIO 2406 on the abaxial surface of the leaf of an Araceae at more than 1 m above the ground. The female UNIRIO 2406 was dissected and showed large oocytes with large amount of vitellum. A few oocytes were measured showing diameter 1.2 ± 0.1 mm (n=5) .

None of the three specimens was found in a bromeliad, all of them being on the vegetation above the ground. However, because of the size of the eggs measured, we believe that this species deposits its eggs in bromeliads, which positions the new species in the group of bromeligenous species together with D. brevipollicatus , D. carvalhoi , D. berthalutzae , D. krausae , and D. stawiarskyi .