Brachyhypopomus pinnicaudatus

discussion

Remarks: Traditional taxonomically formatted description in Hopkins (1991), but necessary elements of a new species description all appeared first in Hopkins et al. (1990), thereby making the name available from that publication. Lectotype is specimen intended by Hopkins (1991) to be holotype.

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

distribution

Distribution: Eastern South America from Catatumbo River basin, Orinoco and Guianas to La Plata River basin; Amazon River basin in Peru (Hopkins, 1991; Albert, Crampton, 2003 a).

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

biology_ecology

Ecological notes. In the Amazon basin Brachyhypopomus pinnicaudatus occurs primarily in floodplain systems of intermediate conductivity (30 - 90 μScm- 1) and high conductivity (90 - 250 μScm 1), especially those with turbid water. Records for low-conductivity (5 - 30 μScm- 1) clearwater and blackwater rivers are mostly confined to near their confluence with major whitewater rivers (e. g. at the confluence of the rio Negro and rio Tefé with the Amazon River), although specimens are known from the rio Tapajós upstream of its mouthbay (ria) lake. Throughout its range B. pinnicaudatus is usually encountered in floating or rooted macrophytes along the margins of lakes, channels and swamps (Crampton, 1996 a; 1998 a; 2011; Crampton & Albert, 2006; Crampton & Ribeiro, 2013; de Queiroz et al., 2013; Hopkins, 1991). Brachyhypopomus pinnicaudatus is able to tolerate seasonal or intermittent hypoxia by undertaking aerial gill respiration (Crampton, 1998 b; Hopkins, 1991). Hopkins (1991) describes the nature of aerial gill respiration of B. pinnicaudatus: “ We noted in containers not oxygenated by bubbling, H. pinnicaudatus would rise to the surface every few minutes, take bubbles of air and lo

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 i and 38. Meristic and morphometric data for examined specimens presented in Tables 2 - 5 and 18. Body moderate to deep in depth. Head short to moderate in length and moderate to deep 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 in size. Upper jaw with slight to moderate sigmoidal angle between premaxillary and maxillary portions in lateral view. No accessory electric organ over operculum. Pectoral fin of moderate width, pectoral-fin rays 13 - 16 (median of 15 in populations from coastal drainages of French Guiana; mode of 14 in population from rio Amazon of Brazil). Precaudal vertebrae 18 - 22 (mode of 20 in populations from coastal drainages of French Guiana; mode of 19 in population from rio Amazon of Brazil), including 1 - 2 transitional vertebrae. Anal-fin origin slightly (<0.25 HL distance) anterior to, or near, tip of pectoral fin. Anal-fin rays 177 - 196 (median of 184 in populations from coastal drainages of French Guiana; mode of 190 in population from rio Am

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