ABSTRACT.âA new species of hylid frog, from the genus Scinax, is described from Ilha de Porcos Pequena at the southern coast of SaËo Paulo State, ...
Journal of Herpetology, Vol. 41, No. 2, pp. 271–275, 2007 Copyright 2007 Society for the Study of Amphibians and Reptiles
A New Island Species of Scinax (Anura; Hylidae) from Southeastern Brazil CINTHIA A. BRASILEIRO,1,2 HILTON M. OYAMAGUCHI,3
AND
CELIO F. B. HADDAD4
1
Museu de Histo´ria Natural, C.P. 6109, Universidade Estadual de Campinas, 13083-000 Campinas, Sa˜o Paulo, Brasil 3 Departamento de Ecologia, Universidade de Sa˜o Paulo, C.P. 11461, 05422-970 Sa˜o Paulo, Sa˜o Paulo, Brasil 4 Departamento de Zoologia, Universidade Estadual Paulista, C.P. 199, 13506-900 Rio Claro, Sa˜o Paulo, Brasil
ABSTRACT.—A new species of hylid frog, from the genus Scinax, is described from Ilha de Porcos Pequena at the southern coast of Sa˜o Paulo State, southeastern Brazil. The new species belongs to the Scinax perpusillus species group and is diagnosed by the following set of characters: moderate-size (males 16.2– 18.8 mm SVL, female 18.8–20.6 mm SVL); canthus rostralis distinct and well defined; V-shaped depression between nostrils; eyes protruding and prominent, glandular skin surface of legs. This new species is found only on Ilha de Porcos Pequena, an island of approximately 24 ha and, therefore, is threatened because of restricted range size and susceptibility to habitat modification.
Scinax Wagler, 1830, is the second largest genus within Dendropsophini (Faivovich et al., 2005). It ranges from southern Mexico to eastcentral Argentina, and the majority of the species occurs in tropical and subtropical areas with a high diversification in the Atlantic Forest of southeastern Brazil (Faivovich, 2002). The genus Scinax contains 91 recognized species (D. R. Frost, Amphibian Species of the World, version 3.0, available online at http:// research.amnh.org/herpetology/amphibi/index. php, 2006) arranged into two principal clades: catharinae and ruber (Faivovich, 2002). The catharinae clade is composed of the Scinax perpusillus group and the S. catharinae group, and the ruber clade is composed of the Scinax ruber group, the Scinax rostratus group, and the Scinax uruguayus group (Faivovich et al., 2005). The S. perpusillus group was first proposed by Peixoto (1987) and includes small species that reproduce exclusively in bromeliads and are distributed in Atlantic tropical coastal forest, ranging from Espı´rito Santo to Santa Catarina, Brazil. Currently eight species are recognized in the S. perpusillus group: Scinax alcatraz, Scinax atratus, Scinax arduous, Scinax littoreus, Scinax melloi, S. perpusillus, Scinax v-signatus (D. R. Frost, Amphibian Species of the World, version 3.0, available online at http://research.amnh. org/herpetology/amphibi/index.php, 2006), and Scinax peixotoi (Brasileiro et al., 2007). Two of these species are endemic to Brazilian islands: S. alcatraz occurs in Alcatrazes and S. peixotoi occurs in Queimada Grande Island. Both islands are approximately 35 km from the coast. Speciation in this habitat presumably occurred subsequent to 2 Corresponding Author. E-mail: cinthia_brasileiro@ yahoo.com.br
population isolation with sea level changes in the past. Because of their exclusive dependence on the water accumulated in bromelids for reproduction, species of Scinax in the perpusillus group can survive and speciate where others species of anurans are not capable of surviving or reproducing. Based on recently collected specimens, we describe a new island species of Scinax, belonging the S. perpusillus species group from Ilha de Porcos Pequena, off the northern coast of Sa˜o Paulo State, Municipality of Ubatuba, southeastern Brazil. MATERIALS AND METHODS All specimens examined are deposited in the following collections: CFBH (C. F. B. Haddad collection, Departamento de Zoologia, Universidade Estadual Paulista, Rio Claro, SP, Brasil), EI (E. Izecksohn collection, Departamento de Biologia Animal, Instituto de Biologia, Universidade Federal Rural do Rio de Janeiro), MZUSP (Museu de Zoologia, Universidade de Sa˜o Paulo, Sa˜o Paulo, SP, Brasil), ZUEC (Museu de Histo´ria Natural, Universidade Estadual de Campinas, SP, Brasil), ZUFRJ (Departamento de Zoologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro), and WCAB (W. Bokerman collection at the Museu de Zoologia, Universidade de Sa˜o Paulo, Sa˜o Paulo, Brasil). We measured the following from 29 specimens to the nearest 0.01 mm with digital calipers: snout–vent length (SVL), head length (HEL), head width (HW), thigh length (THL), tibia length (TBL), foot length (FL), and hand length (HL). We also measured eye diameter (ED), tympanum diameter (TD), interorbital distance (IOD), eye–nostril distance (END), and internarial distance (IND), using a stereo-
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FIG. 1. Scinax faivovichi, adult male in life from Ilha de Porcos Pequena, municı´pio de Ubatuba, Sa˜o Paulo, Brazil.
microscope with a micrometric ocular. All measurements follow Heyer et al. (1994) and Duellman et al. (1997). Webbing formulae follow Savage and Heyer (1967) as modified by Myers and Duellman (1982). Description of shape of the snout was based on the classification of Cei (1980). All specimens collected were euthanized, fixed in 10% formalin, and transferred to 70% ethanol for permanent curation. To test differences between sexes, we used a ttest to compare mean values of SVL. We carried out statistical analyses using Statistica 6.0, with a significance level of 5%. Scinax faivovichi sp. nov. Figure 1 Holotype.—CFBH11602 an adult male, collected at Ilha de Porcos Pequena (23u25920.60S;
44u51919.60W), Municipality of Ubatuba, Sa˜o Paulo State, Brazil, on 6 October 2004, by C. A. Brasileiro, H. M. Oyamaguchi, N. L. Hulle, and M.T.C. Thome´. Paratopotypes.—CFBH 11604–11609, 11611– 11613, 11615–11617 adult males, collected with the holotype. CFBH 11618–11621 adult males, collected on 29 April 2004 by C. A. Brasileiro, H. M. Oyamaguchi, M. T. Thome´, and E. M. Lucas. CFBH 11603, 11610 and 11614 adult females, collected with the holotype, ZUEC13637–13638 adult males, collected with the holotype. MNRJ 40901 adult females, collected with the holotype. MNRJ 40902–40903 adult males, collected with the holotype. MZUSP 135066–135067 adult males, collected with the holotype. Diagnosis.—A moderate-sized species (males 16.2–18.8 mm SVL, females 18.8–20.6 mm SVL) relative to other species in the S. perpusillus group (Peixoto, 1987; Duellman and Wiens, 1992; Faivovich, 2002). The species is characterized by (1) snout protruding in lateral view and subacuminate in dorsal view; (2) head longer than wide; (3) tibia + thigh size same or greater than SVL; (4) canthus rostralis distinct and well defined; (5) warty protuberance in the middle of the canthus rostralis; (6) V-shaped depression between the nostrils; (7) eyes protruding and prominent; (8) arms with dark stripes; (9) webbing lacking between toes I and II; (10) dorsal skin texture slightly rugose; (11) dorsal skin of legs with many glands; (12) in life, dorsum greenish-beige with lightly metallic tones. Description.—The description is based on the collected series of adult males and females. Descriptive statistics are presented in Table 1. Body slender, head longer than wide (Fig. 2A);
TABLE 1. Descriptive statistics of morphometric characters (in millimeters) for males and females of Scinax faivovichi. N 5 number of specimens; x¯ 5 arithmetic mean; SD standard deviation; snout–vent length (SVL), head length (HEL), head width (HW), thigh length (THL), tibia length (TBL), foot length (FL), hand length (HL); eye diameter (ED), tympanun diameter (TD), interorbital distance (IOD), eye–nostril distance (END), and internasal distance (IND). Males (N 5 23)
SVL HEL HW TD ED IOD END IND THL TBL FL HL
Females (N 5 6)
x¯
SD
Range
x¯
SD
Range
17.2 6.9 5.6 0.9 1.9 3.9 2.3 1.8 8.5 9.1 6.6 4.5
0.5 0.3 0.2 0.1 0.2 0.2 0.2 0.1 0.3 0.2 0.3 0.3
16.2–18.0 6.3–7.5 5.1–6.2 0.7–1.1 1.7–2.3 3.5–4.7 2.0–2.6 1.6–1.9 7.8–9.0 8.6–9.9 6.0–7.8 4.0–5.5
19.9 7.7 6.3 2.0 2.1 4.6 2.6 2.0 9.5 10.6 7.6 5.2
1.2 0.3 0.4 0.1 0.2 0.5 0.2 0.2 0.8 0.6 0.5 0.4
18.6–21.7 5.7–7.1 5.7–7.1 1.7–2.1 1.8–2.7 3.9–5.4 2.3–2.9 1.7–2.1 8.4–10.5 9.6–11.2 6.8–8.1 4.6–5.6
C. A. BRASILEIRO ET AL.
FIG. 2. Scinax faivovichi. (A) Dorsal and (B) lateral views of head; ventral views of (C) left hand and (D) foot.
internarial distance smaller than eye–nostril distance and eye diameter; eye diameter smaller than eye–nostril distance; snout sharply protruding in lateral view and acuminate in dorsal view (Fig. 2B); nostrils protuberant; canthus rostralis well defined; loreal region concave; eyes protruding and prominent; tympanum distinct, circular; tympanum diameter approximately half of the eye diameter; weak supratympanic fold from tympanic region to shoulder; discrete subgular vocal sac; the round and large tongue; vomerine teeth in two patches between choanae; choanae medium-size, elliptical. Arms slender; forearms slightly robust, hands larger then forearms; outer metacarpal tubercule cordiform; inner metacarpal tubercule elliptical; subarticular tubercules rounded, single; fingers without webbing; finger lengths I , II , IV , III (Fig. 2 C). Tibia longer than thigh; sum of thigh and tibia same than SVL; feet with round inner metatarsal tubercule; divided outer metatarsal tubercule; subarticular tubercules rounded, single; toe lengths I , II , V , III , IV (Fig. 2 D); foot webbing formula I-II 2+ 3 + III 2 2 3 + IV 3 + 22 V (Fig. 2 D). Dorsal and ventral skin texture slightly rugose. Comparison with other species.—Scinax faivovichi differs from all species of the perpusillus
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group by possessing head longer than wide (wider than long in the other species), the Vshaped depression between nostrils (absent in the other species), and the brown undersurface of tarsus and foot (not brown in the other species). From S. alcatraz, S. faivovichi differs by its smaller size (S. alcatraz males: 19.7–24.4 mm SVL; females 27.0–29.8 mm SVL), more protruding snout, more triangular head, more prominent eyes, canthus rostralis more evident and defined, loreal region concave (not concave in S. alcatraz), arms with dark stripes, and dorsum more ornamented. Scinax faivovichi can be differentiated from S. arduous by its smaller size, less prominent eyes, more protruding snout (in ventral and dorsal views), head longer than wide, and less rugose dorsal skin texture. Scinax faivovichi can be distinguished from S. atratus by its more slender body, more prominent eyes, canthus rostralis more evident and defined, less rugose dorsal skin texture, arms and forearms with dark stripes, and gular region with dark spots. Scinax faivovichi differs from S. littoreous by its smaller size; canthus rostralis more evident and defined, dorsal skin texture more rugose, finger disks more developed, loreal region more curved, venter with a few dark spots (in S. littoreous it is white), arms and forearms with dark stripes, and more ornamented dorsum pattern. From S. melloi, S. faivovichi differs by its larger size (S. melloi males: 15.9–17.00 mm SVL N 5 10; pers. obs.), more rugose dorsal skin, inner metacarpal tubercle less keratinized, snout more protruding, more prominent eyes, and larger head. Scinax faivovichi differs from S. perpusillus by its more slender body shape, more protruding snout, and smoother dorsal skin. Scinax faivovichi differs from S. peixotoi by its more slender body, more prominent eyes, snout more protruding, canthus rostralis more evident, brownish dorsum color (silvery in S. peixotoi), more prominent eyes, and canthus rostralis more evident. S. faivovichi differs from S. v-signatus by its smaller size, head smaller and narrower, canthus rostralis more evident, smoother dorsal skin texture, and no evident V-shaped dark mark on dorsum. Color in life.—Dorsum greenish-beige with metallic tones; interorbital dark brown bar; dark brown line on the canthus rostralis, upper eyelids, and supratympanic fold; wide bright vertebral stripe; one or two brown bars originating at edge of each eye and running posteriorly until near the inguinal regional; hidden portion of shanks with irregular yellow flash color spots; iris golden with a horizontal black bar. Color in preservative.—Dorsum varies from light cream to brown. Interorbital bar and
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vertebral stripe are variable; in some individuals they are not evident and in others very dark. Likewise, the thicknesses of the canthus rostralis line and of the dorsolateral stripes are also variable. Bars on dorsum of arms vary in number and brown color intensity. Stripes on thighs, from inguinal region to knee, varying in intensity and position. Throat has dark spots, sometimes aggregated to form patches. Undersurfaces of arms, hands, fingers, and thighs are white, with very few spots; undersurfaces of tibiae, feet, and toes are brown. Measurements of the holotype (mm).—SVL 16.8, HEL 7.1, HW 5.7, TD 0.8, ED 2,0, IOD 4.2, END 2.4, IND 1.8, THL 8.3, TBL 8.9, FL 6.7, and HL 4.5. Sexual dimorphism.—Females lack vocal sac and vocal slits. Generally, the dorsum color of females is darker than that of males. Females were larger than males (t 5 7.97, df 524, P, 0.01). Natural history and conservation.—We visited Ilha de Porcos Pequena three times during the period of 2004–05; visits occurred during the months of April, October, and December. We observed calling activity of the new species in all months; however, in April few males were calling. Males are nocturnal, calling from bromeliad leaves. Generally, they call with the body vertical and heads pointing up. Females were also found on bromeliad leaves. The species is abundant on the island, especially on rainy and hot nights. We observed tadpoles in bromeliad axils during October and December, suggesting that breeding season is coincident with early summer rains in September/October. Given its extremely restricted range and habitat specificity, we propose that S. faivovichi is susceptible to extinction because of habitat modification or disturbance. Currently, the species is abundant on the island where they can be found at high densities. Nonetheless, this species is restricted to the Ilha de Porcos Pequena, a privately-owned island still covered by native preserved Atlantic Forest. However, this island does not have any legal conservation status under federal laws. Therefore, it is urgent to alter its conservation category. Considering its small distribution and the absence of any enforcement, S. faivovichi should be in the category the IUCN Red List of Threatened Animals (IUCN, available online at http:// www.redlist.org, 2006). Geographic distribution.—Scinax faivovichi is known only from Ilha de Porcos Pequena (23u259210S; 44u519200W), a 24-ha island approximately 0.74 km from the northern coast of Sa˜o Paulo Sate, Brazil.
Etymology.—The specific name honors J. Faivovich for his contribution to the systematic of hylids and particularly of the genus Scinax. Acknowledgments.—We thank Instituto de Biocieˆncias at the Universidade de Sa˜o Paulo, Parque Estadual da Serra do Mar–Picinguaba, and Instituto de Biologia da Conservac¸a˜o for logistical support; FAPESP (00/12339-2, 01/ 13341-3, 04/10199-2), National Science Foundation, Fundac¸a˜o O Botica´rio para Protec¸a˜o da Natureza, and Idea Wild for financial support, and IBAMA for collecting permits (02027. 021071/03-24). N. L. Hulle, E. M. Lucas, M. T. C. Thome´, and K. R. Zamudio assisted with fieldwork. V. Bonelli and L. R. S. Pinto permitted to visit the island. We thank J. Somera for the line drawings, and H. Zaher (MZUSP) and O. L. Peixoto (EI- URRJ) for facilitating examination of Scinax perpusillus species group under their care. K. R. Zamudio commented on earlier drafts of the manuscript; G. R. Smith and one anonymous reviewer provided helpful suggestions. CAB acknowledges FAPESP (03/06014-1) for postdoctoral fellowships, and HMO acknowledges CNPq for graduate funding. CFBH thanks CNPq for the research fellowship. LITERATURE CITED BRASILEIRO, C. A., C. F. B. HADDAD, R. J. SAWAYA, AND M. MARTINS. 2007. A new and threatened species of Scinax (Anura; Hylidae) from Queimada Grande Island, southeastern Brazil. Zootaxa 1391:47–55. CEI, J. M. 1980. Amphibians of Argentina. Monitore Zoologico Italiano (NS) Monografia 2:1–609. DUELLMAN, W. E., AND J. J. WIENS. 1992. The status of the hylids frog genus Ololygon and the recognition of Scinax Wagler, 1830. Occasional Papers of the Museum of Natural History, University of Kansas 151:1–23. DUELLMAN, W. E., I. DE LA RIVA, AND F. R. WILD. 1997. Frogs of the Hyla armata and Hyla pulchella groups in the Andes of South America with definitions and analysis of phylogenetic relationships of Andean groups of Hyla. Scientific Papers, Natural History Museum of the University of Kansas 3: 1–41. FAIVOVICH, J. 2002. A cladistic analysis of Scinax (Anura: Hylidae). Cladistics 18:367–393. FAIVOVICH, J., C. F. B. HADDAD, P. C. A. GARCIA, D. R. FROST, J. A. CAMPBELL, AND W. C. WHEELER. 2005. Systematic review of the frog family Hylidae, with special reference to Hylinae: phylogenetic analysis and taxonomic revision. Bulletin of the American Museum of Natural History 294:1–240. HEYER, W. R., M. A. DONNELLY, R. W. MCDIARMID, L. C. HAYEK, AND M. S. FOSTER. 1994. Measuring and monitoring biological diversity: standard methods for amphibians. Smithisonian Institution, Washington, DC.
C. A. BRASILEIRO ET AL. MYERS, C. W., AND W. E. DUELLMAN. 1982. A new species of Hyla from Cerro Colorado, and other tree frog records and geographical notes from western Panama. American Museum Novitates 2752:1–32. PEIXOTO, O. L. 1987. Caracterizac¸a˜o do grupo ‘‘perpusillus’’ e revalidac¸a˜o da posic¸a˜o taxonoˆmica de Ololygon perpusilla perpusilla e Ololygon perpusilla vsignata (Amphibia, Anura, Hylidae). Arquivos da Universidade Federal Rural do Rio de Janeiro 10:37–49. SAVAGE, J. M., AND W. R. HEYER. 1967. Variation and distribution in tree-frog genus Phyllomedusa in Costa Rica, Central America. Beitrage zur Neotropischen Fauna 5:111–131. Accepted: 19 January 2007.
275 APPENDIX 1
Additional Specimens Examined Scinax alcatraz (topotypes): CFBH 10457–10463; Scinax arduous (topotypes): EI (two individuals); Scinax atratus: (topotypes): EI (WCAB 49641); Scinax littoreous (topotypes): EI 7570/71; Scinax melloi (topotypes): MZUSP 110639, 110648, 110664, 110666 (Tereso´polis, RJ, Brazil), MZUSP 105826, 105829,105835, ´ rga˜os, RJ, Brazil), EI 6945, 6948; 105846 (Serra dos O Scinax peixotoi (holotype and paratotypes): CFBH 9437–9440 (Queimada Grande, SP, Brazil); Scinax perpusillus (topotype): CFBH 1465, WCAB 12859; Scinax v-signatus (topotypes): MZUSP 105921, 105926, ´ rga˜os, RJ, Brazil). 105954, 105959, 76492 (Serra dos O
