Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Gymnotiformes
(Knifefishes) > Sternopygidae
Etymology: Archolaemus: Greek, archo = anus + Greek, laimos = throat (Ref. 45335).
Environment / Climate / Range
Freshwater; benthopelagic. Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 43.5 cm TL male/unsexed; (Ref. 39524)
Morphology | Morphometrics
soft rays: 193 - 222. Distinguished from other congeners in having the following combination of characters: gape relatively long and rictus extending posteriorly beyond the vertical through the posterior naris; length of coronomeckelian bone less than 20% the length of Meckel’s cartilage; length of the posterior ceratohyal 1.5 times the length of the ventral hypohyal; approximately six irregularly distributed teeth on the internal surface of the endopterygoid; anteroposterior length of premaxilla greater than the transverse width; teeth on the dentary restricted to the anterior half or slightly more of the dorsal margin; depth of the caudal filament 5.0-6.5% CL; presence of a narrow dark stripe along the lateral line and a broad dusky to dark band of pigmentation overlying the basal pterygiophores of the anal fin; pectoral-fin rays 19-22; total number of anal-fin rays 193-222 (Ref. 93148).
South America: Previously known only from the Tocantins drainage in Brazil, but has recently been reported in many localities of the Amazonas basin, Rio Branco and Amapa, Brazil.
Its elongated, laterally compressed body is completely covered with scales and is without a caudal fin (Ref. 27188).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Mago-Leccia, F., 1994. Electric fishes of the continental waters of America. Fundacion para el Desarrollo de las Ciencias Fisicas, Matematicas y Naturales (FUDECI), Biblioteca de la Academia de Ciencias Fisicas. Matematicas y Naturales, Caracas, Venezuela. vol. 29 . 206 p. (Ref. 26457)
IUCN Red List Status (Ref. 96402)
CITES (Ref. 94142)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates of some properties based on models
Phylogenetic diversity index (Ref. 82805
= 0.5156 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00398 (0.00151 - 0.01051), b=3.03 (2.80 - 3.26), based on LWR estimates for this (Sub)Family-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 (23 of 100) .