Translator Disclaimer
1 April 2009 Brachyhypopomus bullocki, a New Species of Electric Knifefish (Gymnotiformes: Hypopomidae) from Northern South America
Author Affiliations +
Abstract

We describe the new species Brachyhypopomus bullocki (Gymnotiformes: Hypopomidae) from the río Orinoco basin of Colombia and Venezuela as well as the Takutu River/rio Branco-rio Negro basin of Guyana and Brazil. Among its congeners, B. bullocki most closely resembles Brachyhypopomus brevirostris (Steindachner, 1868) in possessing an elongated caudal filament which may reach up to 45% TL in reproductive males, in having wide, evenly spaced saddles of pigment over the dorsum connecting to lateral bands of pigment along the abdominal flanks, and in having a mesocoracoid bone. This new species is distinguished from B. brevirostris and other members of the genus by a large eye (15.5–19.2% of head length), a short abdomen usually with 12 pre-caudal vertebrae, and poorly ossified third and fourth branchiostegal rays that are enlarged distally, producing a bulbous appearance of the opercular region. The electric organ discharge waveform of B. bullocki is biphasic, 0.9–1.6 milliseconds in duration, and the pulse rate varies from 20–80 Hz.

New taxon: Brachyhypopomus bullocki Sullivan and Hopkins

John P. Sullivan and Carl D. Hopkins "Brachyhypopomus bullocki, a New Species of Electric Knifefish (Gymnotiformes: Hypopomidae) from Northern South America," Proceedings of the Academy of Natural Sciences of Philadelphia 158(1), 183-192, (1 April 2009). https://doi.org/10.1635/053.158.0109
Published: 1 April 2009
JOURNAL ARTICLE
10 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top