Bledius Leach from southern Brazil (Coleoptera, Staphylinidae, Oxytelinae)

Abstract

The species of Bledius Leach, 1819 live in unvegetated, sunny and moist sand adjacent to rivers, lakes and oceans, where they feed on algae and diatoms. Both adults and larvae make burrows in the soil and can be detected by the cast or tumulus left on surface above the entrance of the burrows. Some seacoastal species live in the intertidal zone, and they remain in the burrow during high tide, in an air bubble. An extensive report about the natural history of the genus is found in Herman (1986). Bledius comprises 462 species worldwide (Herman, pers. comm.) placed in 34 species groups, of which seven are in the Neotropical region (mandibularis, aequatorialis, emarginatus, semiferrugineus, forcipatus, punctatissimus and bonariensis groups) (Herman 1986). Herman (2001), in his world catalog of the Staphylinidae, listed ten Bledius species from Brazil, but only B. bonariensis Bernhauer, 1912 was reported from southern Brazil, Rio Grande do Sul; the other nine species are from the north and west in Amazonas and Mato Grosso States. However, in studies focusing on the ecology of the Atlantic beaches in southern Brazil, three species (B.

Ocorrência de três espécies do gênero Bledius Leach, 1819 (Coleoptera, Staphylinidae, Oxytelinae) nas praias arenosas expostas do Paraná, Brasil.

“…Os espécimes coletados nas Ilhas de Superagüi e Peças foram dissecados e montados (Caron & Ribeiro-Costa, 2007), os coletados nas demais localidades estão conservados em álcool 70%.…”

Distribuição espacial e temporal de espécies de Bledius (Coleoptera, Staphylinidae) em praias arenosas no sul do Brasil

“…Estes coleópteros constroem tocas superficiais (de 5 a 200 mm de profundidade) que podem ser reconhecidas através de pilhas hemisféricas ou traços sinuosos de areia seca aglutinadas na entrada. Locais com densa população podem apresentar numerosos rastros, deixando a superfície do sedimento mole e pulverulenta (herman, 1972, 1986souza & Gianuca, 1995;caron & ribeiro-costa, 2007).…”

“…Recentemente, outras duas espécies, Bledius hermani Caron & Ribeiro-Costa, 2007e B. fernandezi Bernhauer, 1939, têm sido reportadas para a Região Sul (borzone et al, 1996;borzone & souza, 1997;caron & ribeirocosta, 2007;Gandara-martins et al, 2010). Estas três espécies foram encontradas em locais próximos à zona supralitoral de praias arenosas expostas (souza & Gianuca, 1995;borzone et al, 1996;borzone & souza, 1997;Gandara-martins et al, 2010).…”

First record of Bledius caribbeanus Blackwelder, 1943 (Coleoptera: Staphylinidae: Oxytelinae) from Brazil and distributional extension of B. hermani Caron and Ribeiro- Costa, 2007

“…However, after a recent revision of the species of Bledius recorded from sandy beaches of Brazilian coast, Caron and Ribeiro-Costa (2007) These two species, B. caribbenaus and B. hermani, are morphologically very similar and mainly differences are higher size, elytra entirely black and sternite VII with just two prominent setae in B. caribbeanus, whereas B. hermani has pale yellow elytra with a basal and usually subapical median brownish spot and sternite VII with eight prominent setae arranged in a transverse row near the apex (Caron and Ribeiro-Costa 2007). The former species had its distribution restricted to Caribbean Sea (Jamaica, Dominican Republic and Trinidad and Tobago) (Frank and Ahn 2011), whereas the latter had been recorded to Brazilian south coast (Rio Grande do Sul and Paraná) (Caron and Ribeiro-Costa 2007;Gandara-Martins et al 2010). These samplings represent the first record of B. caribbeanus in Brazil and extend the known geographic distribution of B. hermani in approximately 2,000 km northwards (Figure 1).…”

“…Along Brazilian coast, studies dealing with sandy beaches insects are scarce and were mainly carried out at south region (Gianuca 1997;Schreiner and Ozorio 2003;Caron and Ribeiro-Costa 2007;Rosa et al 2008;Gandara-Martins et al 2010). In this way, further studies addressing the composition of sandy beach insects will be needed to help us understand the real diversity as well the distributional pattern of Bledius species along Brazilian coast.…”