Melanophryniscus dorsalis ( Mertens, 1933 ) Cruz & Caramaschi, 2003

Cruz, Carlos Alberto Gonçalves & Caramaschi, Ulisses, 2003, TAXONOMIC STATUS OF MELANOPHRYNISCUS STELZNERI DORSALIS (MERTENS, 1933) AND MELANOPHRYNISCUS STELZNERI FULVOGUTTATUS (MERTENS, 1937) (AMPHIBIA, ANURA, BUFONIDAE) 1, Boletim Do Museu Nacional Nova Série Rio De Janeiro - Brasil 500, pp. 1-11 : 2-9

Melanophryniscus dorsalis ( Mertens, 1933) , new status

( Figs.1-5 )

Dendrophryniscus stelzneri dorsalis MERTENS, 1933 .

Melanophryniscus stelzneri dorsalis – GALLARDO, 1961; BRAUN, 1978; BRAUN & BRAUN, 1980; CÉSPEDEZ, 1997; CÉSPEDEZ & ALVAREZ, 2000; CÉSPEDEZ & MOTTE, 2001.

Diagnosis – A medium sized species of the M. stelzneri group, diagnosed by the following characters: (1) SVL 20.5-24.2mm in males, 23.1-24.8mm in females; (2) head broader than long; (3) skin on dorsal and lateral surfaces of body with corneous spines on shallow warts, and additional scattered spines directly on the skin of head and dorsal surfaces of members; (4) ground color of dorsum, loreal region, flanks, and venter dark brown; (5) a distinct, fragmented clear brown stripe on dorsal midline from head to urostile region; (6) two small pale yellow blotches on the gular region, at both corners of mandible; (7) variable pale yellow blotches on the chest, just at the insertion of the arms, belly, and ventral surfaces of forearms and thighs.

Description – General aspect robust, bufonoid ( Fig.1 ). Head broader than long; head width nearly 30% of SVL; head lacking cranial crests; snout short, narrow, slightly projecting beyond the anterior margin of mouth, rounded in dorsal and lateral views ( Figs.2-3 ); canthus rostralis rounded; loreal region vertical, slightly concave; nostrils very small, situated at near tip of snout, directed anteriorly; IND approximately 80% of UEW, 63% of IOD, and equals END; UEW about 74% of IOD; ED 1.4 times IND, 1.1 times UEW, and approximately 80% of IOD; tympanum concealed; vocal slits present in males; tongue much longer than wide, with posterior margin free, rounded; choanae small, rounded, largely separated.

Arms slender, lacking ulnar folds; axillary membrane absent. Hand ( Fig.4 ) with fingers long, slender; length of fingers I<II<IV<III; tip of fingers narrow, rounded, not differentiated as discs; fingers not fimbriated; webbing absent. Outer palmar tubercle moderately sized, rounded; inner palmar tubercle small, rounded, approximately a half of the outer tubercle; subarticular tubercles developed, rounded, but some divided mainly on fingers III and IV; supernumerary tubercles present. Legs short, robust, lacking tarsal folds; THL slightly smaller than TL; sum of THL and TL approximately 70% of SVL. Foot ( Fig.5 ) with toes slender; length of toes I<II<V<III<IV; tip of toes narrow, rounded, not differentiated as discs; toes slightly fimbriated, barely one third webbed; web border indented. Inner metatarsal tubercle large, prominent, ovoid; outer metatarsal tubercle large, rounded, approximately equal in size to inner metatarsal tubercle; subarticular tubercles developed, subconical; supernumerary tubercles poorly developed.

Skin on dorsal and lateral surfaces of body with corneous spines on shallow warts; additional scattered spines directly on the skin of head and dorsal surfaces of members; ventral skin finely granulose with scattered spines on belly; ventral surface of thighs granulose and spinulose. Cloacal opening directed posteriorly at mid-level of thighs.

In preservative (70% ethanol), ground color of dorsum, loreal region, flanks, and venter dark brown; a distinct, complete or fragmented clear brown stripe on dorsal midline from head to urostile region; two small pale yellow blotches on the gular region, at both corners of mandible; the pale yellow color is also observed on the chest, just at the insertion of the arms, as variable blotches on belly, ventral surfaces of forearms and thighs, and palmar and plantar surfaces.

Variation – Variations in measurements are presented in table 1 . The midline dorsal stripe is poorly developed or absent in some specimens.

Geographic distribution – Coastal region of Brazil, from southern of the State of Santa Catarina, in Imbituba (28°14’S, 48°40’W), to the northern of the State of Rio Grande do Sul, in Torres (29°20’S, 49°43’W). BRAUN (1978) and BRAUN & BRAUN (1980) refer the occurrence of this species delimited to the coastal line between Laguna (28°28’S, 48°46’W), State of Santa Catarina, and Tramandaí (29°59’S, 50°08’W), State of Rio Grande do Sul, Brazil. CESPEDEZ (1997) extended the range for this species to Dept. Apostoles (27°51’S, 55°46’W), Province of Misiones, Argentina.

Melanophryniscus dorsalis

– BRAZIL: SANTA CATARINA: Imbituba, Praia de Itapirubá ( MNRJ 27337-27341 ). RIO GRANDE DO SUL: ( MNRJ 3024 ); Torres ( MNRJ 3022 , 3037 , 27342-27346 , AL-MN 450 , EI 4233 ).

Figures

Fig.1- Melanophryniscus dorsalis (Mertens, 1933) (MNRJ 27337). Dorsal and ventral views.

Melanophryniscus dorsalis (Mertens, 1933) (MNRJ 27337): fig. 2- dorsal view of head; fig. 3- lateral view of head; fig. 4- hand; fig. 5- foot. Scale bar = 5mm.