Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Gymnotiformes
(Knifefishes) > Hypopomidae
Etymology: Brachyhypopomus: Greek, brachys, eia = short + Greek, hypo = under + Greek, poma, -atos = cover (Ref. 45335); bullocki: Named for Theodore Holmes Bullock, a pioneer of the comparative neurobiology of both invertebrates and vertebrates.
neurobiology of both invertebrates and vertebrates.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical
South America: Orinoco basin in Venezuela and Colombia; rio Branco drainage in Guyana and Brazil, as well as in the upper rio Negro near the mouth of the rio Branco, but is not known from elsewhere in the Amazon system, or in the Guianas.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 22.1 cm TL male/unsexed; (Ref. 81045)
Morphology | Morphometrics
soft rays: 196 - 233. Can be distinguished by the following combination of features: elongated caudal filament reaching up to 45% TL in reproductive males; 6-11 wide, evenly spaced saddles of pigment over dorsum connecting to lateral bands; mesocoracoid bone present; large eye, 15.5-19.2% HL; short abdomen, usually with 12 pre-caudal vertebrae (range 11-13); poorly ossified third and fourth (outermost) branchiostegal rays, much enlarged distally, covering distal portions of the first two branchiostegal rays externally and contributing to bulbous appearance of opercular region (Ref. 81045).
Inhabits clear, shallow, standing water in open savanna, or savanna mixed with stands of Mauritia palm. Collected in the vegetation along the banks of small pools fed by steams. Occurs inactive during the day among the stems and roots of emergent grasses and sedges. Encountered only in very low conductivity water (<25 ?S/cm) where it usually co-inhabits with Brachyhypopomus brevirostris. The electric organ discharge waveform is biphasic, 0.9-1.6 milliseconds in duration, and the pulse rate ranges from 20 to 80 Hz (Ref. 81045).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Sullivan, J.P., 2009. Brachyhypopomus bullocki, a new species of electric knifefish (Gymnotiformes: Hypopomidae) from northern South America. Proc. Acad. Nat. Sci. Phila. 158:183-192. (Ref. 81045)
IUCN Red List Status (Ref. 115185)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01000 (0.00244 - 0.04107), b=3.04 (2.81 - 3.27), in cm Total Length, based on all LWR estimates for this body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.2 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
Vulnerability (Ref. 59153
): Low vulnerability (11 of 100) .