Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Gymnotiformes
(Knifefishes) > Hypopomidae
Etymology: Akawaio: Named for Akawaio Amerindians that populate the region of the upper Mazaruni and to recognize their valuable help while studying the fishes of their lands. A masculine noun.; penak: From the Akawaio name ‘penak’, which is apparently used unambiguously for this species. A masculine noun in apposition.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical
South America: endemic to the upper Mazaruni River in Guyana.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 21.7 cm TL male/unsexed; (Ref. 94087)
Morphology | Morphometrics
soft rays: 173 - 199. Can be diagnosed by the following characters: coracoid with a foramen; opercle with concave posterior margin; one ossified basibranchial; absence of postpectoral or humeral accessory electric organs; 14 total pectoral-fin rays (ii-iii) (shared with ranges of some Brachyhypopomus species0; 173-199 anal-fin rays (shared with ranges of few species of Brachyhypopomus and Microsternarchus); snout length 24.7-32.6% HL; five pectoral radials, in some individuals four partially fused to five (shared with Hypopomus species); mesopterygoid with short or reduced ascending process (shared with Microsternarchus species); mesocoracoid bridge absent (shared with most species of Brachyhypopomus, Microsternarchus and Racenisia); and 17 precaudal vertebrae (shared with some Brachyhypopomus species) (Ref. 94087).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Maldonado-Ocampo, J.A., H. López-Fernández, D.C. Taphorn, C.R. Bernard, W.G.R. Crampton and N. Lovejoy, 2013. Akawaio penak, a new genus and species of Neotropical electric fish (Gymnotiformes, Hypopomidae) endemic to the upper Mazarumi River in the Guiana Shield. Zoologica Scripta (Ref. 94087)
IUCN Red List Status (Ref. 119314)
CITES (Ref. 115941)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 1.0000 [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) .