Gastrotheca prasina, Jr & Vechio & Recoder & Carnaval & Strangas & Damasceno & Sena & Rodrigues, 2012

Jr, Mauro Teixeira, Vechio, Francisco Dal, Recoder, Renato Sousa, Carnaval, Ana Carolina, Strangas, Maria, Damasceno, Roberta Pacheco, Sena, Marco Aurélio De & Rodrigues, Miguel Trefaut, 2012, Solution NMR Structure of CalU 16 from Micromonospora echinospora, Northeast Structural Genomics Consortium (NESG) Target MiR 12, Zootaxa 3437, pp. 1-23 : 4-9

Gastrotheca prasina sp. nov.

( Figs. 1–3 )

Holotype: MZUSP 147059 ( Figs 1–3A ), an adult male from Reserva Biológica da Mata Escura (16°20'30.08"S, 40°59'49.17"W, WGS 84, 989 m a.s.l.), Jequitinhonha municipality, Minas Gerais state, Brazil, collected on December 6 th 2009 by M. Teixeira Jr., M. A. de Sena, R. S. Recoder, M. T. Rodrigues, R. P. Damasceno and A. C. Carnaval; field number MTR 17236.

Paratopotypes: MZUSP 147060–63 , MZUSP 147065 , adult males, collected from December 6 th 2009 to January 9 th 2010; field number MTR 17248, MTR 17459–61 and MTR 17707, respectively . MZUSP 147064 , an adult female, collected on December 6 th 2009; field number MTR 17462. Same collectors as holotype .

Etymology: The specific epithet is a Latin word derived from prasinus (=green), which refers to the greenish general body color of this new species.

Diagnosis: Comparative list of diagnostic features are presented in Table 1. (1) A large-sized species (SVL 97.2mm in females, 79.3–89.6mm in males); (2) head length smaller than head width (HL about 90% of HW); (3) skin co-ossified to the skull; (4) snout truncate in dorsal view and in profile; (5) tympanum vertically elliptical, TD about 85% of ED; (6) upper eyelid without a distinctive tubercle; (7) crescent order of length of fingers, II<IV<I<III; (8) fingers not webbed; (9) calcar appendage absent; (10) toes with vestigial webbing; (11) dorsal skin shagreened; (12) background coloration orangish green with a dark brown subocular bar; (13) posterior edge of skull bones straight; (14) presence of whitish nuptial excrescences.

Description of the holotype: An adult male (SVL= 83.11mm). Head wider than long; snout truncate in dorsal and lateral views. Canthal ridge sharp, straight; nostrils anterior, directed laterally. Loreal region slightly concave with an upper groove delimitate by the canthal ridge; lips thin, rounded. Vomerine teeth in two series, slightly oblique, between choanae, widely separate, internal edge placed posteriorly. Vocal slits present, lateral to tongue; vocal sac single, subgular. Tongue ovoid, slightly narrow. Interorbital space slightly concave; eyes prominent. Posterior edge of skull bones straight. Upper eyelid without a distinctive tubercle. Tympanum elliptical, TD 95% ED; tympanic annulus distinct, tympanic membrane smooth, with a supratympanic fold. Arms slender, forearm slightly hypertrophied. Axillary membrane absent; hand large. Fingers long, in crescent order of size, II<IV<I<III. Subarticular tubercles relatively small, rounded; a large, elliptical thenar tubercle; palmar tubercle bifid, supernumerary tubercles present, small. Discs large, elliptical; diameter of Finger III disk 77% of TD; whitish nuptial excrescences present. Circumferential grooves and pad present. Fingers not webbed. Hind limbs relatively short, THL 43% of SVL, TL 45% of SVL, and sum of THL and TL 89% of SVL. Tarsal fold absent. Outer metatarsal tubercle small, elliptical; inner metatarsal tubercle moderately large, ovoid. No calcar appendage. Foot with long toes, in crescent order of size, I<II<III<V<IV. Toe discs rounded to elliptical, smaller than those of fingers; diameter of fourth toe disc 56% of TD. Subarticular tubercles relatively small, rounded; supernumerary tubercles small. Toes with vestigial webbing, slightly fringed. Dorsal skin shagreened; skull skin strongly co-ossified; flanks, belly, throat, chest and ventral surfaces of hind and forelimbs granulate. Dorsal surfaces of hind and forelimbs granulate. Forearm with an outer well defined line of granules, tarsus with an outer poorly defined line of granules.

Color: Background dorsal coloration greenish with a slightly anteriorly oriented darker green chevron and scattered darker green over dorsum; head orangish green with a curve interorbital green bar; dark brown blotch posterior to nostril contiguous with a brown line along canthal groove, loreal region green; canthal ridge and lips orangish. Dark brown infraorbital bar, postorbital dark brown stripe passing over tympanum and extending posteriorly into a lateral wide black stripe interrupted after arm insertion. Flanks with green and brown coloration, and ventrolaterally with black vermiculations and small yellowish irregular markings, that extends over the arm. Hindlimbs dorsal surfaces orangish green with transverse green bars than enters anterior surface of thighs with a whitish background coloration and blackish transverse bars; posterior surfaces of thigh with dark vermiculations and yellowish irregular markings; forearm with transverse green bars; dorsal surfaces of hands and feet orangish; throat and chest dark grey, belly light gray with lateral dark vermiculations. Ventral surfaces of arms and legs dark grey with light markings. Sub-cloacal region black with white spots. In preservative green tones turned into gray tones, general coloration is dark gray; yellowish and orangish colorations turned into light gray tones.

Measurements of the holotype (mm): SVL=83.11; HL=27.94; HW=31.53; ED=6.65; TD=6.1; END=8.63; ESD=12.71; THL=36.29; TL=38.18; FTL=51.41; 3FD=4.7; EW=6.23; IOS=14.03; 4TD=3.55.

Variation: Small color variation was observed among individuals, mostly affecting the visibility of the dorsal chevrons. Some specimens possessed homogeneous green dorsal surfaces, others had a distinctive chevron-shaped spot, while a few showed an intermediate color pattern. Variation in measurements is presented in Table 2.

Advertisement call: A series of four to eight calls are emitted by males at a rate of 0.82 call/sec. Each call consists of two pulsed notes, the first averaging 485ms in length (432–543ms), the second 172ms (149–187ms). Dominant frequency of the first note is ca. 1370 Hz (1350–1405 Hz) and the second note 1331 Hz (1240–1515 Hz). The first note has about 15.3 pulses (14–17) and the second about 7.3 (6–8). Notes and pulses are slightly frequencymodulated and no harmonic structure is visible ( Fig. 4 ). Occasionally only the first note is given.

Comparison with other species (data from congeners are presented in parenthesis): G. prasina sp. nov. can be distinguished from all other Gastrotheca from the Atlantic Forest with the exception of G. fissipes , G. megacephala and G. recava sp. nov. by its large size, 97mm in females, 79.3–89.6mm in males (combined SVL of the other species 32.6–77.2mm in females, 27.7–70.0mm in males), tympanum large, vertically elliptical, with diameter about 80–95% of eye diameter (tympanum small to medium sized, circular, 50–71% of eye diameter), toes vestigially webbed (toes distinctively webbed), dorsal skin shagreened (smooth, weakly granulate in G. flamma ). G. prasina sp. nov. can be further distinguished from G. pulchra and G. flamma by the absence of a tubercle on the upper eyelid and by lacking an appendage on calcars (present). From G. albolineata , G. microdiscus , and G. pulchra , it can be distinguished by its skull skin extensively co-ossified (not co-ossified). It can be distinguished from G. megacephala by its narrower head 37–39% of SVL (40–43% of SVL), larger body size 79.3–89.6mm in males (71.9–78.7mm in males), tympanum diameter in males 5.54–6.83mm (6.9–8.1mm in males), and several advertisement call features, including the duration of first note 432–543ms (350ms), the duration of the second note 149–187ms (60ms), the number of pulses in the first note 14–17 (9) and in the second note 6–8 (5), the occurrence of notes and pulses slightly frequency-modulated (notes end pulses not frequency modulated), and the fact that the first note is the most intense one (second note is the most intense). From G. fissipes , G. recava sp nov., and G. megacephala , it can be distinguished by its greenish background dorsal coloration (brownish background coloration). From G. recava sp nov. and G. fissipes , it can be distinguished by having the posterior edged of parietal bones roughly straight ( Fig. 5A ) (posterior edge of skull bones extensively arched inwards, and arched outwards, respectively; Figs. 5C, D ). Additionally from G. recava sp. nov. it can be distinguished by the presence of a dark brown infraorbital bar (absent, replaced by a dark brown temporal coloration contiguous with a dark brown stripe that extends through the lateral surfaces of the body) and an advertisement call consisting of pulsed notes with 6 to 17 pulses (24 pulses).

Natural history and distribution: Males were commonly found calling from the vegetation at nighttime after rainy days. Calls were heard soon after the sunset. Males were heard and seen while calling from inside ground bromeliads between 18h–19h; it is possible that they hide in the axils of these plants during the day. From 20h–21h, they were heard and seen at lower branches of small trees emerging from large clusters of bromeliads. At ca. 22h, males were calling from higher branches (2–3 m high) in small trees, close to bromeliad clusters. One female was found inside a bromeliad tank, carrying more than 16 eggs. Although ground bromeliads were also present inside the forest, every individual was either found or heard in isolated patches of open vegetation with bare ground and sandy soil ( Fig. 6 ). The species was mainly found in this kind of habitat, a transitional formation between forest and high-altitude grassland that resembles the coastal restingas, but that is found in the region only above 900 m a.s.l. of elevation.

The currently known geographical range of this species is thus restricted to these patches, and the bromeliads occupied by individuals were also used by other frog species such as Phyllodytes luteolus and Bokermanohyla sp. This is the second record of Gastrotheca in the state of Minas Gerais ( Moura et al. 2012) and the inland-most report at this latitude; most Atlantic Forest Gastrotheca species have coastal distributions ( Fig. 7).

Figures

FIGURE 1. Holotype of Gastrotheca prasina sp. nov. (MZUSP 147059): Dorsal (left) and ventral (right) views.

FIGURE 2. Holotype (MZUSP 147059) of Gastrotheca prasina sp. nov.: Dorsal (A), Lateral (B) views of the head; Foot (C) and hand (D). Scale bar = 5 mm.

FIGURE 3. Living holotype (MZUSP 147059) of Gastrotheca prasina sp. nov. (A), living paratopotypes hiding inside a bromeliad (B), calling with extended vocal sac (C), and a female carrying eggs on its pouch (D).

FIGURE 4. Advertisement call of Gastrotheca prasina sp. nov.: (A) Oscillogram containing four calls and; (B) An oscillogram of a section comprising a single call; (C) Spectrogram of the same call; (D) Amplitude spectrum of the same call. Calls were recorded about 20:00 h on 6th December 2009, air temperature was about 21ºC.

FIGURE 5. Comparison of posterior edge of skull in (A) Gastrotheca megacephala, (B) G.prasina sp. nov., (C) G. recava sp. nov., and (D) G. fissipes, externally (left) and internally (right). Externally visible edge of skull bones represented by a black dashed line. Bones: 1= sphenethmoid; 2=nasal; 3=frontoparietal; 4=squamosal.

FIGURE 6. Habitats occupied by Gastrotheca prasina sp. nov.: (A) A general view of the landscape at RBME; note hills slopes covered with forests and patches of open sparse vegetation on their top; (B) a detail of the open vegetation that dominate the summit, showing the sandy soil with bare ground, and dense clusters of bromeliads; (C) and the bromeliad in which individuals of Gastrotheca prasina sp. nov. were found.