Bledius caribbeanus Blackwelder, 1943

Castro, Jessica Cristina De, Caron, Edilson & Rosa, Leonardo Cruz Da, 2016, Update on the Brazilian coastal species of Bledius Leach (Coleoptera: Staphylinidae: Oxytelinae) with the description of two new species, Zootaxa 4111 (2), pp. 145-157 : 152-155

Bledius caribbeanus Blackwelder, 1943 vs. B. hermani Caron & Ribeiro-Costa, 2007

( Figs. 5 , 22–31 )

Bledius caribbeanus Blackwelder, 1943:113 (Description, type locality: “ Tobago, seashores 3 miles southwest of Scarborough”). For a complete references list see Herman (2001); Frank & Ahn 2011:31 (distribution); Rosa et al. 2013:450 (error of distribution on the Brazilian northeastern states); Rosa et al. 2015: 251 (error of mention).

Bledius hermani Caron & Ribeiro-Costa, 2007:455 (Description, type locality: “ Brazil, Paraná, Guaraqueçaba, Superagui”). Rosa et al. 2013:450 (distribution on the Brazilian northeastern states, Alagoas and Rio Grande do Norte); Rosa et al. 2015: 251 (mention).

Bledius caribbeanus and B. hermani are two morphologically similar species, however they show very distinct distributions, the first species is distributed in Jamaica, Dominican Republic and Trinidad and Tobago ( Frank & Ahn 2011), and B. hermani occurs in all the Brazilian coast, from the states of Rio Grande do Norte to Rio Grande do Sul ( Rosa et al. 2013).

The only differences between the two species known to literature were described by Caron & Ribeiro-Costa (2007), one being the number of prominent setae on the sternite VII. This difference was not confirmed in this study; therefore, we suggest that this difference is not valid. Also, the fine setae around the apex of the accessory gland represented in Fig. 23 ( Caron & Ribeiro-Costa 2007) is unfounded, probably being a mistake.

Although, some differences from literature have been validated, one being the size, Bledius caribbeanus is slightly larger (1.7–2.5mm) than B. hermani (1.76–1.84mm), and in relation to color of the body, being B. caribbeanus entirely dark brown to black, while B. hermani is reddish to dark brown, with the elytra yellowish with brown spots on the internal margin ( Fig. 5 ) ( Caron & Ribeiro-Costa 2007).

With the review of the female paratype of Bledius caribbeanus deposited in FMNH and females of B. hermani (DZUP), new differences between the two species were identified. Bledius caribbeanus has the antennomeres 3–5 as wide as long, being the antennomere 3 with obtuse sides and the antennomere 11 almost two times longer than wide ( Fig. 22 ), while B. hermani has the antennomeres 3–5 wider than long, being the antennomere 3 with parallel sides and the antennomere 11 equal to slightly longer than wide ( Fig. 27 ).

In relation to the terminalia, Bledius caribbeanus has the anterior margin of tergite VIII with a median emargination ( Fig. 23 , arrow), while B. hermani has the anterior margin of tergite VIII with sublateral emarginations ( Fig. 24 , arrow). Besides, the sternite VIII of B. hermani has the median area of the posterior border weakly sclerotized ( Fig. 26 , arrow), not being observed in B. caribbeanus ( Fig. 25 ). Also, the tergite X of B. caribbeanus has basal angles more rounded, apical margin slightly curved and it is longer than wide ( Fig. 28 , arrow), as B. hermani has basal angles less rounded, apical margin truncate and it is as wide as long ( Fig. 29 , arrow).

The spermatheca could not be seen on the type material of B. caribbeanus , but based on the drawings of Herman (1972, Fig. 115), the two spermathecas appear to be similar in shape ( Fig. 31 ). Unfortunately, the male genitalia ( Fig. 30 ) of the two species was not compared because no male was found of B. caribbeanus .

In this study, we extended the distribution of Bledius hermani for a new Brazilian state, Rio de Janeiro, and a new locality in the state of Sergipe.

About Bledius caribbeanus , in this study, the distribution of B. caribbeanus is corrected, not occurring in Brazil and being restricted to the Caribbean Sea (see remarks under B. depressus , sp. nov.).

Examined material. Bledius caribbeanus Blackwelder, 1943 . FMNH: One specimen. “(1) Guadeloupe / BasseTerre/ 30.X.1935 ” [White label, locality printed and date handwritten]. (2) “Sta 77. A/ Blackwelder” [White label, printed with number handwritten]. (3) “ParatypeNo/ 52372/ U.S. N.M. [Orange label, printed with numbers handwritten].

Bledius hermani Caron & Ribeiro-Costa, 2007 . DZUP: 25 specimens. Two specimens: “ BRAZIL, PB, Conde, P. do/ Carneiros/ 07º15,28’ S 34º54,29’ W / 15-II-2010 / L. Sousa-Souto, col.” [White label, printed]. Three specimens: “BR-AL-Pontal do Coruripe/ 10º10’20”S 36º10”12”W/ 8-X-2011 / Ambrosi, B e L. Souto, col.” [White label, printed]. Ten specimens: “ BRAZIL, SE, Baixinho Imp.,/ P. Aruana/ 11º01,82’ S 37º04,65’ W / 23-I-2010 / L. C. Rosa, col.” [White label, printed]. New locality record. Ten specimens: “ BRASIL, RJ, Búzios/ Barra do Una/ 04-VII-2012 / M.P. Mendes, col.” [White label, printed]. New locality record.

Figures

FIGURES 1 – 6. Habitus. 1, Bledius bonariensis; 2, B. fernandezi; 3, B. borzonei, sp. nov.; 4, B. externus; 5, B. hermani; 6, B. depressus, sp. nov..

FIGURES 22 – 31. Bledius caribbeanus and B. hermani. 22. Antenna, B. caribbeanus. 23 – 24. Tergite VIII. 23, B. caribbeanus (detail of median emargination); 24, B. hermani (detail of sublateral emarginations). 25 – 26. Sternite VIII. 25, B. caribbeanus; 26, B. hermani (detail of weakly sclerotized posterior border). 27. Antenna, B. hermani. 28 – 29. Tergite X. 28, B. caribbeanus (detail of rounded basal angles); 29, B. hermani (detail of less rounded basal angles). 30. Aedeagus, B. hermani, lateral view. 31. Spermatheca, B. hermani. Scale = 0.1 mm.