Berosus exiguus (Say, 1825)

Deler-Hernandez, Albert, Fikacek, Martin & Cala-Riquelme, Franklyn, 2013, A review of the genus Berosus Leach of Cuba (Coleoptera, Hydrophilidae), ZooKeys 273, pp. 73-106 : 77-79

Berosus exiguus (Say, 1825) Figures 2 a–g 11

Hydrophilus exiguus Say, 1825: 189.

Berosus exiguus (Say). - Van Tassell 1966: 145 (unpublished PhD thesis: redescription, identification key, recorded from Cuba). - Testa and Lago 1994: 26 (diagnosis, bionomic and distribution notes, identification key). - Hansen 1999: 86 (catalogue). - Peck 2005: 48 (checklist). - Epler 2010: 12.19 (identification key, taxonomic notes). - Fernández et al. 2010: 28 (checklist). For complete references and synonymy see Hansen (1999)

Type locality.

USA: Virginia, Chincoteague Island.

Material examined.

CUBA: Isla de la Juventud: 1 ex. (in alcohol) (BSC-E): Punta del Este, Laguna Cayamás, 21°33'43"N, 82°33'18"W, 3 m a.s.l., 23.v.2006, leg. Y. S. Megna, 00165. Camagüey: 2 exs. (in alcohol) (BSC-E): Nuevitas, Cayo Sabinal, Laguna permanente [permanent pool], 21°38'6.1"N, 77°10'8.2"W, 5 m a.s.l., 06.v.2010, leg. O. Bello, 00153; 2 exs. (dry-mounted) (NMPC): Cayo Sabinal, permanent lagoon, 21°38'6.1"N, 77°10'8.2"W, 5 m a.s.l., 06.v.2010, leg. Y. Torres. Santiago de Cuba: 1 ex. (in alcohol) (BSC-E): San Miguel de Parada, Laguna temporal [temporal pool], 20°11'2.50"N, 75°46'17.7"W, 1 m a.s.l., 29.v.2009, leg. A. Deler-Hernández, 00136; 4 exs. (in alcohol) (BSC-E): San Miguel de Parada, Laguna temporal [temporal pool], 20°11'2.50"N, 75°46'17.7"W, 1 m a.s.l., 05.ix.2009, leg. A. Deler-Hernández, 00151; 2 exs. (dry-mounted) (NMPC): San Miguel de Parada, temporal lagoon, 20°11'2.50"N, 75°46'17.7"W, 1 m a.s.l, 05.ix.2009, leg. A. Deler-Hernández.

Published Cuban records:Pinar del Rio: unspecified locality ( Van Tassell 1966: 149, Map 21).

Diagnosis.

Habitus as in Figs 2a, b. Body length 3.0-3.7 mm. Head testaceuos, pronotum testaceous without median darker spots, punctation not darkened, elytra testaceous with irregularly arranged ill-defined slightly darker spots. Elytral apices entire and rounded in both sexes. Mesoventral process highly laminar, triangular in shape, anterior tooth large projecting posteriad (Fig. 2c). Abdominal ventrite 1 with median keel developed on basal half only. Emargination of abdominal ventrite 5 rectangular, without teeth (Fig. 2g) (in non-Cuban specimens, a very small medial tooth is present: Testa and Lago 1994). Aedeagus (Figs 2 d–f) with median lobe only slightly shorter than parameres, with apex curved ventrad, bearing two series of long setae on dorsal surface.

Distribution.

Eastern USA (from New York to Florida, westwards reaching to Illinois, Indiana, Mississippi and Oklahoma), Bahamas ( Young 1953; Hansen 1999; Peck 2005) and Cuba. In Cuba, it is known from the central and eastern region.

Habitat.

Berosus exiguus is mainly restricted to brackish waters in coastal regions. Cuban specimens have been collected in temporary brackish pools with clear water, abundant organic detritus on the bottom and associated aquatic riparian vegetation.