Bluntnose Knifefish

Uso

Uso a nivel regional (Orinoquia): ornamental (Ajiaco-Martínez et al. 2012)

Peces de la cuenca del río Pauto, Orinoquia colombiana

distribution

Distribution: Widespread through cis-Andean South America from Orinoco to La Plata River (Crampton et al., 2016 b).

Checklist of Gymnotiformes (Osteichthyes: Ostariophysi) and catalogue of primary types

biology_ecology

Ecological notes. Brachyhypopomus brevirostris is an ecologically cosmopolitan species, and varies from being locally rare to exceptionally abundant in lentic and slow-flowing environments throughout its range (Alves-Gomes, 1997; Crampton, 1996 a; 1998 a; Crampton & Albert, 2006; Crampton & Ribeiro, 2013; de Queiroz et al., 2013; Hopkins & Heiligenberg, 1978; Mol, 2012). It occurs in seasonally inundated floodplains (in floating rafts of meadows and shallow newly-flooded forests), along the margins of rivers (in emergent and floating vegetation), in ephemeral or perennial swamps (in vegetation or submerged debris), and in terra firme forest and savanna streams (in emergent and submerged vegetation, leaf litter and debris, and in marginal root mats and holes). In the lowland Amazon, B. brevirostris occurs in low-conductivity blackwater and clearwater streams, river margins, and floodplain systems (ca. 5 - 30 μScm- 1), and also high-conductivity whitewater river margins and floodplain systems (ca. 90 - 250 μScm- 1), as well as in waters of intermediate conductivity. Nonetheless, it is most abundant in low-conductivity systems. Brachyhypopomus brevirostris is less tolerant of prolonge

A taxonomic revision of the Neotropical electric fish genus Brachyhypopomus (Ostariophysi: Gymnotiformes: Hypopomidae), with descriptions of 15 new species

description

Description. Head and body shape, and pigmentation illustrated in Figs. 1 e and 17. Meristic and morphometric data for examined specimens presented in Tables 2 - 5 and 10. Body shallow to moderate in depth. Head short to moderate in length and shallow to moderate in depth. Dorsal profile of head straight to slightly convex from occiput to snout, ventral profile of head approximately straight between operculum and snout. Snout rounded. Eye moderate to large in size. Upper jaw with moderate sigmoidal angle between premaxillary and maxillary portions in lateral view. No accessory electric organ over operculum. Gill filaments on first gill arch 40 - 63 (median 55, n = 38). Pectoral fin narrow to broad in width, pectoral-fin rays 15 - 20 (mode of 17 in populations from upper Madeira (Guaporé), Orinoco, and upper Paraguay; mode of 18 in a population from central Amazon). Precaudal vertebrae 18 - 21 (mode of 19 in populations from upper Madeira, central Amazon, and upper Paraguay; mode of 20 in a population from Orinoco), including 1 - 2 transitional vertebrae. Anal-fin origin slightly (<0.25 HL distance) anterior or posterior to, or near, tip of pectoral fin. Anal-fin rays 226 - 293; ran

A taxonomic revision of the Neotropical electric fish genus Brachyhypopomus (Ostariophysi: Gymnotiformes: Hypopomidae), with descriptions of 15 new species