Dendrophryniscus lauroi Miranda-Ribeiro, 1926

Cruz, Carlos Alberto Gonçalves, Caramaschi, Ulisses, Fusinatto, Luciana Ardenghi & Brasileiro, Cinthia Aguirre, 2019, Taxonomic review of Dendrophryniscus brevipollicatus Jiménez de la Espada, 1870, with revalidation of D. imitator (Miranda-Ribeiro, 1920) and D. lauroi Miranda-Ribeiro, 1926, and description of four new related species (Anura, Bufonidae), Zootaxa 4648 (1), pp. 27-62 : 38-42

Dendrophryniscus lauroi Miranda-Ribeiro, 1926 , new status, revalidated

( Figs. 6–8 )

Dendrophryniscus brevipollicatus lauroi Miranda-Ribeiro, 1926 .

Dendrophryniscus b. travassoi P. Miranda-Ribeiro, 1955 — nomen nudum.

Dendrophryniscus brevipollicatus— Cochran 1955 (part); Izecksohn 1994 (part).

Lectotype. MNRJ 394 , adult female ( Fig. 6 ), collected at Municipality of Angra dos Reis (22 o 54’S, 44 o 20’W, Datum WGS 84; 25 m altitude), State of Rio de Janeiro, Brazil, by Lauro Travassos.

Miranda-Ribeiro (1926), in the original description, referred to two typos (syntypes). P. Miranda-Ribeiro (1955) found only one specimen, which was designated lectotype. Currently the lectotype ( SVL 18.2 mm) is in poor condition, fade, with a strong transversal sulcus caused by an early line tied behind the head, and right leg broken.

Diagnosis. The species is characterized by: (1) medium size for the genus ( SVL 14.5–19.9 mm in males, 19.0 mm in female); (2) body slender; (3) snout rounded in dorsal view; (4) canthus rostralis straight; (5) elliptical set of unpigmented shallow granules posterior to the corner of mouth; (6) presence of numerous granules on upper eyelid surfaces, with the external margin slightly prominent; (7) tip of the third and fourth fingers laterally expanded (8) skinfold poor developed on the articulation of the first and second phalanges of the fingers II, III, and IV; (9) male with moderate nuptial pad with minuscule and pigmented horny asperities on finger I; (10) fingers not fringed nor webbed.

Comparisons with other species. Dendrophryniscus lauroi is distinguished from D. proboscideus by the smaller size ( SVL 14.5–19.9 mm in males of D. lauroi ; SVL 39.2–46.4 mm in males of D. proboscideus ); D. lauroi is distinguished from D. krausae and D. stawiarskyi by the slender body with uniform shape (robust and enlarged posteriorly in those species); D. lauroi is distinguished from D. davori sp. nov., D. brevipollicatus , D. haddadi sp. nov., D. imitator , D. izecksohni sp. nov., D. krausae , D. oreites , D. organensis , D. proboscideus , and D. skuki by the snout rounded in dorsal view (snout mucronate in dorsal view in D. davori sp. nov., D. brevipollicatus , D. haddadi sp. nov., D. imitator , D. izecksohni sp. nov., and D. organensis ; snout truncate in dorsal view in D. krausae , D. oreites , and D. proboscideus ; snout long, narrow, spatulate, with parallel lateral borders and rounded tip in D. skuki ); by the canthus rostralis straight, D. lauroi is distinguished from D. berthalutzae , D. brevipollicatus , D. haddadi sp. nov., D. imitator , D. izecksohni sp. nov., D. oreites , D. organensis , D. proboscideus , and D. skuki (canthus rostralis slightly curved); D. lauroi presents an elliptical set of unpigmented shallow granules posterior to the corner of mouth (elliptical set of white, pronounced granules in D. brevipollicatus ; longitudinal set in D. berthalutzae , D. krausae , D. leucomystax , and D. oreites ; two pronounced granules in D. imitator ; absent in D. carvalhoi , D. haddadi sp. nov., D. organensis , D. proboscideus , D. skuki , and D. stawiarskyi ); D. lauroi presents the surfaces of upper eyelid with numerous granules and with the external margin slightly prominent (surfaces of upper eyelid with numerous granules densely distributed and with a conspicuous margin in D. brevipollicatus and D. izecksohni sp. nov.; surfaces of upper eyelid with few granules sparse and external margin prominent in D. haddadi sp. nov. and D. imitator ; surfaces of upper eyelid with few granules sparse and external margin conspicuous in D. davori sp. nov.); D. lauroi is distinguished from D. davori sp. nov., D. berthalutzae , D. carvalhoi , D. haddadi sp. nov., D. imitator , D. krausae , D. oreites , and D. stawiarskyi by the tip of the third and fourth fingers laterally expanded (poorly or not expanded in those species); D. lauroi is distinguished from D. brevipollicatus by the presence of a skinfold poorly developed on the articulation of the first and second phalanges of the fingers II, III, and IV (well developed in this species); D. lauroi is distinguished from D. davori sp. nov., D. carvalhoi , D. izecksohni sp. nov., D. leucomystax , and D. stawiarskyi by the presence of moderate nuptial pad in male (absent in D. leucomystax , very developed in D. davori sp. nov., D. carvalhoi , D. izecksohni sp. nov., and D. stawiarskyi ); D. lauroi is distinguished from D. brevipollicatus by the fingers not fringed nor webbed (slightly fringed and webbed only at base in this species), from D. krausae (fingers not fringed and webbed only at base), and from D. izecksohni sp. nov. and D. jureia sp. nov. (fingers fringed and webbed about one third).

Original description (freely translated from Portuguese). “B— D. b. lauroi —Specimens from Angra dos Reis, collected by Dr. Lauro Travassos present two types, with weakening of xyphisternum, absence of supranasal groove, and body more slender.

Description of topotype. MNRJ 58298, adult male, collected at Ilha Grande (23 o 10’S, 44 o 09’W, Datum WGS 84, 100 m altitude), Municipality of Angra dos Reis, State of Rio de Janeiro, Brazil, on 03 January 1997.

Body slender, elongated ( Fig. 7 ); head triangular, longer than large, head length 30.7% of SVL; snout rounded in dorsal view, acute in lateral view ( Fig. 8 ); snout 49.1% of head length; nostrils not protuberant, small, elliptical, located laterally near the tip of snout, slightly below the canthus rostralis; internarial distance 55.1% of eye to snout distance; eye diameter 75.8% of eye to snout distance and 91.6% of interorbital distance; eye slightly protuberant; canthus rostralis straight; loreal region vertical; vocal sac indistinct; choanae small, circular, very far from each other; tongue long, narrow. Vocal slits present. Arms robust, forearms more robust than upper arms; hand with fingers slender, not fringed nor webbed, distal end of III and IV fingers slightly expanded laterally; finger I enlarged, covered by moderate nuptial pad with minuscule pigmented horny asperities; relative lengths of fingers I< II < IV < III; subarticular tubercles single, rounded; outer metacarpal tubercle large, rounded; inner metacarpal tu- bercle rounded, slightly smaller than subarticular tubercles; supernumerary tubercles present, small and scarce, skin fold poorly developed on the articulation of the first and second phalanges of the fingers II, III, and IV. Thigh length slightly shorter than tibia length; sum of thigh and tibia lengths 83.5% of snout–vent length. Tarsal length 28% of the snout vent length. Foot with slender toes, not fringed; interdigital webbing only at the base, webbing formulae: I1–2 II 11/2 –3 III2– 21 /2IV 21/2 –2V; distal end of toes globose, not expanded laterally, relative lengths of toes I< II < III <V< IV; subarticular tubercles single, rounded, larger than those of fingers; outer metatarsal tubercle large, approximately rounded; inner metatarsal tubercle large, elliptical; supernumerary tubercles present, small, scarce. Dorsal and lateral surfaces covered by numerous spinulose shallow granules, uniformly distributed, ventral surfaces rugose; presence of numerous granules on upper eyelid surfaces, with the external margin slightly prominent; pres- ence of elliptical set of unpigmented shallow granules posterior to the corner of mouth.

Color in preservative. The color of the lectotype is fade because of the time of preservation, and the body surfaces are homogeneously pale brown, being not possible to observe the body blotches. The topotype presents dorsum pale brown background and brown blotches and bars; a head blotch extending on the upper eyelids, an ‘X’ shaped blotch on the scapular region, and an inverse ‘Y’ shaped blotch on the sacral region; on forearms, one transversal bar and one blotch on elbow; one transversal bar on thigh, tibia, and tarsus, and one blotch on knees and heels; a lateral dark brown stripe from the snout, passing on the eye and reaching the inguinal region, being narrower in the loreal region; ventral surface pale cream, with disperse small brown blotches.

Measurements of topotype. SVL 19.2; HL 5.9; HW 5.7; IND 1.6; ESD 2.9; ED 2.2; IOD 2.4; THL 8.1; TL 8.4; TAL 5.2; FL 6.7.

Variation. Specimens are congruent respecting morphological characters. Variation in size and shape of the brown blotches on dorsal surfaces can be observed. Variation of measurements and descriptive statistics of males and females are presented in Tables 2 and 3. Sexual dimorphism can be observed on SVL (longer in females), on arms (more robust in males), finger I (robust in males), and nuptial pad (on finger I of males). Nuptial pad can be pigmented or not.

Distribution. Dendrophryniscus lauroi is known from the following municipalities ( Fig. 17 ) in the State of Rio de Janeiro, Brazil: Angra dos Reis, Ilha Grande (22 o 10’S, 44 o 09’W, Datum WGS 84; 100 m altitude), Angra dos Reis, Fazenda Floresta (22 o 54’S, 44 o 20’W, Datum WGS 84; 25 m altitude), and Mangaratiba (22 o 59’S, 44 o 06’W, Datum WGS 84; 80 m altitude); and State of São Paulo, Municipality of Bananal (22 o 41’S, 44 o 19’W, Datum WGS 84; 500 m altitude).

Natural history. This species is associated to forested areas and restinga formations, from few meters to 500 m above sea level, and breeds in bromeliads plants, where its larvae develop (D. Vrcibradic and C.A.G. Cruz personal observations). Tadpoles were described in Izecksohn and Cruz (1972) as D. brevipollicatus .

Remarks. An illustration of D. lauroi was presented by Miranda-Ribeiro (1926, fig.72, pg. 138).

Figures

FIGURE 6. Dendrophryniscus lauroi Miranda-Ribeiro, 1926, lectotype, MNRJ 394 (SVL 18.2 mm). Dorsal view.

FIGURE 7. Dendrophryniscus lauroi Miranda-Ribeiro, 1926, topotype, MNRJ 58298 (SVL 19.2 mm). Dorsal and ventral views.

FIGURE 8. Dendrophryniscus lauroi Miranda-Ribeiro, 1926, topotype, MNRJ 58298 (SVL 19.2 mm). Dorsal and lateral views of head, ventral views of hand and foot.

FIGURE 17. Map of geographic distribution of species of Dendrophryniscus brevipollicatus group reviewed in this study. RJ, State of Rio de Janeiro; SP, State of São Paulo.