Scinax pombali , Lourenço, Ana Carolina Calijorne, Carvalho, André Luiz Gomes De, Baêta, Délio, Pezzuti, Tiago Leite & Leite, Felipe Sá Fortes, 2013

Lourenço, Ana Carolina Calijorne, Carvalho, André Luiz Gomes De, Baêta, Délio, Pezzuti, Tiago Leite & Leite, Felipe Sá Fortes, 2013, A new species of the Scinax catharinae group (Anura, Hylidae) from Serra da Canastra, southwestern state of Minas Gerais, Brazil, Zootaxa 3613 (6), pp. 573-588: 576-584

publication ID

http://dx.doi.org/10.11646/zootaxa.3613.6.4

publication LSID

lsid:zoobank.org:pub:99F53949-E344-4A87-AD81-632B08FE6D38

persistent identifier

http://treatment.plazi.org/id/644087B5-A266-132A-FF53-FDDCFAD54B1E

treatment provided by

Plazi

scientific name

Scinax pombali
status

sp. nov.

Scinax pombali  sp. nov.

( Figs. 1 and 2)

Holotype. MNRJ 49479, an adult male (21.1 mm SVL) collected at Ribeirão da Capivara, Chapadão da Babilônia (20 o 36 ’03’’S, 46 o 17 ’ 34.9 ’’W, elevation 987 m), Serra da Canastra, municipality of Capitólio, State of Minas Gerais, Brazil, on 27 August 2007 by A.L.G. Carvalho and colleagues.

Paratypes. MNRJ 49476, 49478, adults gravid females, and MNRJ 49477, adult male, all collected with the holotype. MNRJ 54986, adult male collected at Chapadão da Babilônia, municipality of Capitólio, State of Minas Gerais, Brazil, on 12 November 2004. UFMG 10601 –02, UFMG 10610, adult females collected at Serra de Capitólio, municipality of Capitólio, state of Minas Gerais, Brazil, on 16 February 2012 by F.S.F. Leite. UFMG 10603, UFMG 10611 – 12, UFMG 10616, adult males collected at Serra de Capitólio, municipality of Capitólio, state of Minas Gerais, Brazil, on 16 February 2012 by T.L. Pezzuti.

Diagnosis. The new species is assigned to the genus Scinax  based on the identification of the following morphological synapomorphies suggested by Faivovich et al. (2002): webbing between toes I and II that does not extend beyond the subarticular tubercle of toe I, origin of the m. pectoralis abdominalis at well defined tendons, and m. pectoralis abdominalis overlapping m. obliqus externus. It is assigned to the S. catharinae  species group due to the laterodistal origin of the m. extensores brevis distalis digit III (presumed synapomorphy suggested by Faivovich 2002), and by having developed webbing between toes II and III (the species of the S. perpusillus  group exhibit reduced webbing between toes II and III according to Peixoto 1987 and Faivovich 2002). This small species is diagnosed by: (1) in life, dorsum gray with black blotches bordered by a silver line; a black elliptical spot between the eyes and nostrils; inguinal region and hidden surfaces of thigh with irregular brown blotches on yellow background; (2) snout sub–elliptical in dorsal view; (3) canthus rostralis well marked; (4) lack of externally differentiated inguinal gland; (5) glandular area on medial margin of finger II do not developed to form a distinct nuptial pad; (6) tadpoles with large-sized oral disc and multiseriate marginal papillae on anterior and posterior labium of the oral disc.

Comparison with other species. Scinax pombali  differs from all species of the S. catharinae  species group by its unique dorsal color pattern, with blotches outlined in silver, and by its single black elliptical spot between the eyes and nostrils ( Figure 1). Additional characters diagnosing the new species are listed below.

The new species differs from S. agilis  (n= 4 males and 29 females), S. argyreornatus  (n= 24 males and 19 females), and S. skuki  (n= 22 males and 4 females) by its larger size (SVL of males in Scinax pombali  20.2–25.1, females 28.6–34.9; SLV of males in these species 13.1–17.1mm, females 14.7–25.1mm), and from S. ariadne  (n= 40 males and 9 females) and S. catharinae  (n= 25 males and 16 females) by its smaller size (SVL of males in Scinax pombali  20.2–25.1, females 28.6–34.9; SLV of males in these species 28.8–47mm, females 38–47mm). Scinax pombali  is distinguished from S. aromothyella  (n= 16), S. berthae  (n= 4), S. centralis  (n= 1), S. luizotavioi  (n= 10), S. machadoi  (n= 6), and S. ranki  (n= 3) by the larger size of female (SVL of females in Scinax pombali  28.6–34.9; SLV of female in these species 19.5–30.6mm), whereas females of this species are smaller than those of S. albicans  (n= 9), S. strigilatus  (n= 7), and S. tripui  (n= 5) (SLV of females in these species 36.1–45.5mm). The new species differs from S. muriciensis  (n= 4) by the smaller size of males (SLV of males in this species 27–28.9mm).

Scinax pombali  differs from all species of the S. catharinae  group except S. aromothyella  , S. argyreornatus  , S. berthae  , and S. skuki  by its sub–elliptical snout in dorsal view: the snout in S. ariadne  and S. obtriangulatus  is rounded; in S. albicans  , S. angrensis  , S. flavoguttatus  , S. humilis  , S. littoralis  , S. muriciensis  , S. strigilatus  , S. trapicheiroi  , and S. tripui  is rounded with a mucronate end; in S. agilis  , S. canastrensis  , S. longilineus  , S. rizibilis  , and S. skaios  is subovoid; in S. carnevallii  and S. kautskyi  is mucronate; in S. luizotavioi  is sub-elliptical with a pointed end. Most specimens of S. argyreornatus  and S. skuki  have mucronate snout, but some have sub-elliptical snout, thus we can not differentiate them from the new species by this feature.

The well marked c anthus rostralis distinguishes S. pombali  from S. agilis  , S. albicans  , S. argyreornatus  S. ariadne  , S. aromothyella  , S. berthae  , S. brieni  , S. catharinae  , S. centralis  , S. jureia  , S. machadoi  , S. obtriangulatus  , S. ranki  , S. rizibilis  , S. skuki  , and S. trapicheiroi  (canthus rostralis poorly marked in these species).

The lack of an externally differentiated inguinal gland distinguish Scinax pombali  from S. ariadne  , S. brieni  , S. canastrensis  , S. catharinae  , S. centralis  , S. jureia  , S. hiemalis  , S. longilineus  , S. luizotavioi  , S. obtriangulatus  , S. ranki  , S. rizibilis  , and S. skaios  (particularly hypertrophied in S. centralis  and externally well differentiated in the other species).

The new species differs from S. agilis  , S. albicans  , S. angrensis  , S. aromothyella  , S. carnevallii  , S. catharinae  , S. brieni  , S. humilis  , S. littoralis  , S. luizotavioi  , S. machadoi  , S. obtriangulatus  , S. rizibilis  , S. skaios  , S. trapicheiroi  , and S. tripui  in having a glandular area on medial margin of finger II that does not develop to form a distinct nuptial pad ( S. rizibilis  has hypertrophied nuptial pad; in other species this glandular area is developed forming a distinct nuptial pad that changes the width of the finger II, but the nuptial pad is not hypertrophied).

The inguinal region and hidden surfaces of thigh with irregular brown blotches on yellow background S. pombali  differs from S. agilis  (“without flash color”; Cruz & Peixoto 1982), S. albicans  , (dark brown transversal bars on pale background), S. angrensis  (“dark blotches surrounding the light area”; B. Lutz 1973), S. ariadne  (light brown irregular blotches on violet or pink background), S. brieni  , (“pale blue”; B. Lutz 1973), S. carnevallii  (“whitish with black spots scattered”, Caramaschi & Kisteusmacher 1989), S. catharinae  (dark brown irregular blotches on light blue background), S. flavoguttatus  (brown irregular blotches on orange background), S. heyeri  (“orange-yellow”; Peixoto & Weygoldt 1987), S. hiemalis  (“black blotches on a greenish background”; Haddad & Pombal 1987), S. humilis  (dark irregular blotches on bluish or pale background), S. kautskyii  (“blackish brown with whitish spots”; Carvalho-e-Silva & Peixoto 1991), S. luizotavioi  (light brown irregular blotches on pale background), S. littoralis  (“black bars on a whitish or greenish background”; Pombal & Gordo 1991), S. obtriangulatus  (“dull grayish violet”; B. Lutz 1973), S. ranki  (“greenish with dark blotche”; Andrade & Cardoso 1987), S. skaios  (“brown or pale green with irregular dark brown stripes”; Pombal et al. 2010), S. strigilatus  (“greenish”; Pimenta et al. 2007), S. trapicheiroi  (dark brown irregular blotches on light blue background), and S. tripui  (dark brown irregular blotches on greenish background).

Description of holotype. Body slender and short size. Head longer than wide (40.07 % of SVL). Snout subelliptical in dorsal view and protruding in profile. Nostril located laterally, immediately before the tip of snout, opening directed dorsum–laterally, elliptical, and protruding. Canthus rostralis well marked and nearly concave. Loreal region slant and concave. Eye large, protruding laterally, with diameter 42.42 % of head width. Interorbital and internostril distance 39.09 % and 29.09 % of head width respectively. Tympanum rounded, annulus timpanicus not well defined, with diameter measuring 35.71 % of eye diameter. Supratympanic fold marked and granulated. Tongue large, elongated, unattached in the posterior and laterally borders. Vocal slits present, diagonals, starting from the back of the tongue. Vomerine teeth in two contiguous convex small series of four teeth each, between choanae, though slightly displaced posteriorly. Choanae elliptical. Vocal sac subgular, not expanded externally.

Members slender, with forearms longer than arms. Outer margins of the forearm and tarsus smooth. Hands 29.81 % of snout–vent length. Inner metacarpal tubercle absent and outer metacarpal bilobeted. Subarticular tubercles single and rounded, supernumerary absent. Membranes absent between fingers II and III, rudimental between III and IV, and IV and V. Discs on fingers elliptical, wider than long. Length of fingers II<III=V<IV. Glandular area on medial margin of finger II does not develop to form a distinct nuptial pad. This glandular area extends medially up to the margin of the outer metacarpal tubercle, and distally up to the base of the second subarticular tubercle. Foot 44.63 % of snout vent length. Outer metatarsal tubercle absent and inner single and rounded. Single and conical subarticular tubercles on toe I, others rounded. Supernumerary absent. Length of toes: I<II<V<III<IV. Toes with webbing formula I–II 1 -– 3 III 1 -– 2 2 / 3 IV 2 1 / 2 – 1 -V. Elliptical discs wider than long.

The inguinal regions do not have a externally differentiated inguinal gland. The pectoral fold is absent. The cloacal opening is at upper level of thighs. Skin on dorsum rough. Granular skin on throat, belly, and undersurfaces of thigh.

Color of holotype in preservative. Dorsal coloration gray with shades of silver and brown ( Fig. 1). Interocular region with a triangular shaped black marking bordered by silver line. Dorso-lateral region with a black stripe bordered by a conspicuous silver line, extending from the pre–ocular region to mid–body. Posterior dorsal region with an inverted V-shaped black marking bordered by a conspicuous silver line. Anterior and posterior dorsal surfaces of the arms and legs with transversal black strips. Canthus rostralis with a black strip. A black elliptical spot between the eyes and nostrils. Supratympanic fold with a black strip through all its extension. Light brown dots on belly and throat. Iris gray. The inguinal region is white with irregular brown blotches.

Color in life (based on type series). The same as in preservative, except for the brighter and sharper intensity and contrast and the brown colored iris with dense gold dots. Inguinal region and hidden surfaces of thigh with irregular brown blotches on yellow background ( Figure 1).

Variation of adult specimens. Measurements of the type series are shown in Table 2. Males are slender and smaller than females. Females exhibit more vivid and bright blotches, and a T-shaped mark between the eyes.

Black dorsal-lateral strip in some specimens reaches the inguinal region. Little black elliptical spot between the eyes and nostrils is sharper and darker in females. Inner metacarpal tubercle is single and oval in females. Some male and all females have supranumerical tubercles. The absence of these tubercles in the holotype is likely a preservation artifact. Males and females have variable webbing formula I–II 1 1 / 2– 3 III 1 1 / 2–3 + IV 3 – 1 1 / 2 V; I–II 1 2 / 3 – 3 III 2 - – 3 + IV 3 +– 1 1 / 2 V; I–II 1 1 / 2– 3 III 1 1 / 2–3 + IV 3 -– 1 +V; I–II 2 -– 3 III 2 -– 3 1 / 2 IV 3 -– 1 V.

Etymology. The specific epithet is the singular genitive case of the name Pombal. José P. Pombal Jr. is an important herpetologist that has significantly contributed to our understanding of the taxonomy of the genus Scinax  . We recognize his contribution in the taxonomy of Brazilian anurans and take great pleasure in honoring our teacher and colleague.

Tadpole description. Body depressed (BH/BW = 0.78–0.95) ( Fig. 3 A and 3 B); slightly longer than one third of total length (BL/TL = 0.33–0.37); oval in dorsal view. In lateral view, ventral contour of body flat in the gular region, convex in the abdominal region. Snout rounded in dorsal view (BWN/BWE = 88–95), and sloped to truncated in lateral view. Nostrils rounded, small (ND/BL = 0.01–0.02), dorsally located ( IND /BWN = 0.39–0.47), closer to eyes than to the snout (NSD/ END = 1.18–1.69). Eyes large (ED/BWE = 0.21–0.25), dorsally located (IOD/BWE = 0.69–0.77), dorsolaterally directed. Spiracle single, sinistral, and lateroventral (SDEH/BH = 0.35–0.45); large, posterodorsally projected, visible in dorsal and lateral views; its inner wall free from the body and slightly longer than the external wall; opening located at the posterior third of the body (SED/BL = 0.69–0.80). Intestinal switchback point located at the center of the abdominal region ( Fig. 3 C). Vent tube small with dextral opening, entirely fused to ventral fin. Tail slightly higher than body (MTH/BH = 1.02–1.16); well-developed musculature (TMH/MTH = 0.52–0.65) does not reach the rounded tip of the tail. Dorsal fin low (DFH/TMH = 0.50–0.63), with margin slightly convex, maximum height in the beginning of the distal third of the tail; emerges on posterior third of the body at a low slope; ventral fin with margin convex; origin concealed by vent tube; shorter than dorsal fin (DFH/VFH = 1.18–1.52). Oral disc ( Fig. 3 D) ventrally positioned; large-sized (ODW/BW = 0.71–0.96, measured with oral disc folded); not emarginated; two to three rows of marginal papillae in alternate disposition on its dorsal portion, without a dorsal gap; most papillae long and conical and some bi or trifurcated; lateroventral portion with multiseriate rows of marginal papillae, in unorganized arrangement, differing in papillae size and shape: external rows with smaller and conical papillae; inner rows with rounder, wider and larger papillae, some trapezoidal shaped; rows of submarginal papillae in the lateral portion of the oral disc portion, entering between anterior and posterior parts of the oral disc; few submarginal papillae (three to four) between anterior tooth rows (A 1 and A 2), laterally. Tooth row formula (LTRF) 2 (2)/ 3; all rows long with approximately the same length, and with a variable number of indentations; wide jaw sheaths darkly pigmented; upper jaw sheath “M” shaped and lower sheath "V" shaped. Measurements for all the available developmental stages are shown in Table 3.

Tadpole coloration in life. Body presenting two golden bands, formed by concentration of the golden tiny iridophores, one in the snout region, especially between eyes and nostrils, and other in the posterior third of the body ( Fig. 4 A and 4 B). These bands are broken by a median dark brown irregular stripe that can reach the abdominal region, which is golden (intestine partially visible). In smaller individuals the color pattern is more contrasting. Spiracle tube translucent. Tail muscle light brown. Some individuals present a dark lateral stripe under the dorsal fin in the proximal third of the tail. Fins translucent, with some dark blotches especially in dorsal fin. Iris with golden dots.

Tadpole coloration in preservative. In 10 % formalin, the shiny bands are absent ( Fig. 3 A). The body acquires light brown coloration. The iris loses its golden tones, becoming black.

Comparison with other tadpoles of the S. catharinae  group. Tadpoles of Scinax pombali  are distinguished from all known species of the S. catharinae  group, with exception to S. ariadne  , by the large-sized oral disc and presence of multiseriate marginal papillae on anterior and posterior labium of the oral disc (median to small-sized oral disc and uni to biseriate rows of marginal papillae in most species). Also differs from many species, with exception of S. albicans  , S. angrensis  , S. ariadne  , and S. flavoguttatus  , by the absence of dorsal gap on the row of marginal papillae of the oral disc (present in some species as wide gap, and in others as small gap).

As mentioned for some species of the group ( S. albicans  , S. angrensis  , S. kautskyi  , S. trapicheiroi  , S. machadoi  , S. ariadne  , S. tripui  , and S. flavoguttatus  ) S. pombali  shows a concentration of the golden tiny iridophores between eyes and nostrils, giving it a flashy banding bright pattern, which is absent in S. argyreornatus  , S. berthae  , S. catharinae  , S. hiemalis  , S. humilis  , S. littoralis  , S. luizotavioi  , S. longilineus  , S. obtriangulatus  , S. ranki  , and S. rizibilis  .

Scinax pombali  differs from S. kautskyi  by the dextral vent tube (vent tube positioned medially in this specie), and from S. berthae  by the rounded tail tip and by the upper jaw sheath “M” shaped (tail with a flagellum and jaw sheath arch shaped in S. berthae  ). Tadpoles of S. pombali  also differ from those of S. aromothyella  by the Mshaped upper jaw sheath (arch-shaped upper jaw in this species). It differs from S. catharinae  and S. tripui  by the ventrolateral spiracle (in these species spiracle opens at the body midline).

Scinax pombali  differs from S. ariadne  , S. rizibilis  , and S. machadoi  by LTRF (these species exhibit 2 /3, 2(2)/ 3 (3) and 2 (2)/ 3 (1), respectively). Despite the similarity, S. pombali  differs from S. ariadne  by the rounded snout in dorsal view (very truncated in S. ariadne  ), presence of long, conical, and bi or trifurcated marginal papillae in the dorsal portion of oral disc (absence of differentiated papillae in the anterior labium in S. ariadne  ), trapezoidalshaped and large papillae in the ventral portion of oral disc (absence of differentiated papillae in the posterior labium in S. ariadne  ), rows of submarginal papillae between anterior and posterior parts of oral disc and between anterior tooth rows (absence of submarginal papillae in S. ariadne  ), absence of black blotches in caudal musculature simulating transversal bars (present in S. ariadne  ), and presence of golden bands between nares and eyes (absent in S. ariadne  ).

Distribution, natural history, and comments. Scinax pombali  is known only for the type locality ( Fig. 5). The species was collected in an altered campo rupestre remnant located in the southwestern portion of the State of Minas Gerais, ca. 55 km from the Parque Nacional da Serra da Canastra. This area holds 29 anuran species, including five Scinax  ( S. canastrensis  , S. fuscovarius  , S. machadoi  , S. maracaya  , and S. squalirostris  ) (Haddad et al. 1988). Also, frogs considered endemic to the area had their distribution recently expanded (e.g. Scinax canastrensis  ; Oliveira–Filho & Kokubum 2003; Araújo et al. 2007; Moura & Cazelli 2011). This indicates the need of additional field research, which may reveal not only new populations of already known species, but also new species, as the one described here. Most specimens of Scinax pombali  were collected during the night, when they were in reproductive activity, but four specimens were collected during the day. The specimens were found in the marginal shrubby–arboreal vegetation along a permanent stream (a small gallery-like forest surrounded by campo rupestre vegetation, 987m of elevation). The stream is part of major river system where ponds are formed on the marginal rock surfaces. It is possible that the new taxon described here is syntopic with other congeners in watercourses present along the Serra da Canastra.

Acknowledgements

We are thankful to Dr. H. R. da Silva, Universidade Federal Rural do Rio de Janeiro (UFRRJ) for reading early versions of the manuscript; to C. Cassini (Universidade do Estado de São Paulo) and Sean McKenzie (The Rockefeller University) for linguistic revision of the manuscript; to P. Nascimento for the illustrations included in this paper; to A. L. Silveira for pictures of the preserved adults of Scinax pombali  ; to Ivan Magalhães and Laboratório de Aracnologia, Departamento de Zoologia (ICB/UFMG), for the oral disc photographs. For grants and finantial suport, A.C.C. Lourenço, D. Baêta, and F.S.F Leite are grateful to the National Counsel of Technological and Scientific Development (CNPq), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Fundação Carlos Chagas de Amparo a Pesquisa (FAPERJ), and Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) ANPCyT PICT 2007-2202. Fieldwork was funded by Programa Biota Minas/FAPEMIG, project ‘Anfíbios e répteis da Serra do Espinhaço: preenchendo as lacunas do conhecimento de quatro áreas prioritárias para a conservação da herpetofauna de Minas Gerais’, FAPEMIG/Vale project ‘Taxonomia e distribuição geográfica de anfíbios do Quadrilátero Ferrífero, Minas Gerais: desenvolvendo ferramentas para aumentar a eficiência do processo de licenciamento ambiental’, and Programa Sisbiota/FAPESP ‘Girinos de Anuros da Mata Atlântica, da Amazônia, do Pantanal, do Cerrado e de Zonas de Transição: Caracterização Morfológica, Distribuição Espacial e Padrões de Diversidade (Process 2010 / 52321 - 7).

TABLE 3. Measurements (in mm) of tadpoles of Scinax pombali from Capitólio, state of Minas Gerais, Brazil, for developmental stages 28 – 30 (n = 21) according to (Gosner 1960). For abbreviations, see the text.

Characters Min Max Mean ± SD
TL 33.0 40.8 37.5 ± 2.3
BL 11.6 14.4 13 ± 0.8
TAL 21.1 27.5 24.6 ± 1.7
MTH 7.4 10.1 8.6 ± 0.7
DFH 2.5 3.3 2.9 ± 0.2
VFH 1.9 2.8 2.2 ± 0.2
TMH 4.6 6.0 5.1 ± 0.4
BH 7.2 9.7 8.0 ± 0.6
SL 1.5 2.1 1.8 ± 0.2
SDEH 3.7 4.3 3.3 ± 0.4
SED 8.3 10.6 9.7 ± 0.6
ED 1.8 2.3 2.0 ± 0.1
BW 7.8 10.6 9.2 ± 0.8
BWN 7.1 9.1 8.1 ± 0.6
BWE 7.8 10.0 8.9 ± 0.7
TMW 3.6 5.2 4.4 ± 0.5
END 2.4 3.0 2.7 ± 0.2
ESD 5.3 7.1 6.1 ± 0.5
NSD 3.2 4.5 3.7 ± 0.3
ND 0.5 0.8 0.2 ± 0.1
IND 0.2 0.3 2.2 ± 0.0
IOD 5.8 7.5 6.5 ± 0.5
ODW 6.9 9.0 7.9 ± 0.7

Kingdom

Animalia

Phylum

Chordata

Class

Amphibia

Order

Anura

Family

Hylidae

Genus

Scinax