Pharceonus volcanus Spangler & Santiago-Fragoso, 1992

Maier, Crystal A., 2013, A revision of the Larainae (Coleoptera, Elmidae) of Venezuela, with description of nine new species, ZooKeys 329, pp. 33-91 : 80-82

Pharceonus volcanus Spangler & Santiago-Fragoso, 1992 Figs 5, 85, 86, 87

See Spangler and Santiago-Fragoso 1992 for complete species description and genitalia illustrations.

Material examined.

PANAMA: Chiriqui: "PANAMA, Chiriqui; Volcan (26km W); 1380 m, small brook; at culvert, 3 June1983" "Collectors; P.J. Spangler; R.A. Faitoute; W.E. Steiner" (1 Holotype USNM). VENEZUELA: Zulia State: "VENEZUELA: Zulia; SW of Machiques; 31 XII 05; 435m; 10°03'N, 72°43'W; trib[utary] of Rio Negro" "A.E.Z. Short; P.J. Torres; collectors" (5 specimens SEMC). "VENEZUELA: Zulia State; 10°03.058'N, 72°42.974'W; 435m; Perija National Park; Toromo; 31.xii.2005; leg. A.E.Z. Short; Small stream & seep; AS-06-001" (3 specimens SEMC).

Diagnosis.

This species can be distinguished from all other species of Pharceonus by its small size (3.1-3.5 mm), dark brown color, genitalia (aedeagus + phallobase) of medium width (4.3 × as long as wide), and pronotum with only a shallow transverse impression across apical third (Fig. 87).

Intraspecific variation.

This species varies slightly in color, from dark brown to medium brown, and size, from 3.1-3.5 mm.

Distribution and habitat.

This species is found on roots in small to medium forested streams, and on roots in seeps in the Sierra de Perija in Venezuela (Fig. 5). This appears to be the southern extent of its range. Outside of Venezuela, this species is known from as far north as Costa Rica. Specimens have been collected in leaf packs and in the benthos in shallow streams.

Associated species.

This species was collected at the same sites as following taxa: Oocyclus spp., Anacaena spp., Enochrus spp., Notionotus spp., and Chasmogenus spp. ( Hydrophilidae ), and Hydraenidae .