Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Gymnotiformes
(Knifefishes) > Apteronotidae
Etymology: Porotergus: Greek, poros = porous + Latin, tergum = back, the upper plate or segment in an animal (Ref. 45335); duende: The specific epithet, duende, is the Portuguese for elf or imp, referring to the diminutive size of P. duende. A noun in apposition. Gender masculine.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal; pH range: 6.9 - 7.3. Tropical; 27°C - 32°C (Ref. 83661)
Known from the main channel of the Amazon River in the western portions of the Amazon basin (Rio Negro and Rio Solimões in Brazil, Rio Ucayali in Peru.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 18.4 cm TL male/unsexed; (Ref. 83661); 10.4 cm TL (female)
Morphology | Morphometrics
soft rays: 124 - 142. This species is distinguished from its congeners by the following characted: presence of a light brown body pigmentation (vs. pale straw pigmentation in P. gimbeli, and dark brown in P. gymnotus); one row of conical teeth on the dentary (vs. two); edentulous premaxilla (vs. presence of teeth); ossified second basibranchial (vs. unossified in P. gimbeli, condition unknown in P. gymnotus). It further differs from P. gimbeli by the absence of a distinct swelling on the chin (vs. presence of this structure), the total anal-fin rays (124-142 vs. 171–198), and the prepectoral-fin distance (14.1-17.0% of LEA vs. 10.3-13.5); from P. gymnotus by the distance from the posterior naris to the eye (1.7-3.8% of HL vs. 8.2-11.9), mouth length (12.4-27.4% of HL vs. 28.1-38.7), pectoral-fin length (72.7-89.0% of HL vs. 60.4-70.7) (Ref. 83661).
This species is known mainly from the main channels of large whitewater rivers such as the Rio Solimões(Amazon) and Río Ucayali. In the Tefé region, it was encountered only during the rising water period in January and February, and captured in waters of 2–4 m depth on beaches of alluvial silt and fine sand. Based on examined stomachs of four specimens, this species feeds exclusively on small, autochthonous, benthic insect larvae (of micro-caddis fly, biting midge and beetle). Most specimens had loose sand grains in the stomach (larger than the grains of sand in the caddis fly jackets), suggesting foraging on sandy substrates; one stomach contained many endoparasitic nematodes. All four specimens captured in the Tefé region had maturing, but not fully mature, gonads, suggesting that spawning occur during the rising water period, typical of riverine apteronotids (Ref. 83661).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
de Santana, C. D. and G. R. Crampton, 2010. A review of the South American electric fish genus Porotergus (Gymnotiformes: Apteronotidae) with the description of a new species. Copeia 2010(1):165-175. (Ref. 83661)
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
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00339 (0.00134 - 0.00855), b=3.09 (2.87 - 3.31), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.3 ±0.3 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .