Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Characiformes
(Characins) > Characidae
(Characins) > Incertae sedis
Etymology: Hemigrammus: Greek, hemi = half + Greek, gramma = letter, signal (Ref. 45335); arua: Named for its type locality, lago São Francisco do Alto Aruã, A noun in apposition.
Environment / Climate / Range
Freshwater; benthopelagic; depth range 1 - 2 m (Ref. 81198). Tropical
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 3.0 cm SL male/unsexed; (Ref. 81198)
Morphology | Morphometrics
soft rays: 21 - 25;
Vertebrae: 31. Distinguished from all species of the genus, except Hemigrammus stictus (Durbin), by having a large single humeral spot situated from fifth-sixth to posterior margin of eighth-tenth lateral line scales. Differs from Hemigrammus stictus by having a humeral spot roughly rectangular, higher than wide, with a pronounced upper, anteriorly-oriented extension,
conferring an inverted-comma shape to the blotch (vs. humeral spot roughly rounded, not presenting an inverted-comma shape), and life color pattern presenting unpaired fins orange reddish (vs. caudal fin and caudal peduncle bright red in life, remaining fins translucent) (Ref. 81198).
South America: headwaters of the rio Arapiuns, rio Tapajós basin, and from the adjacent headwaters of the igarapé Juruti Grande, rio Amazonas in Brazil.
Inhabits shallow marginal areas, with abundant aquatic macrophytes, both emergent and non-emergent (Ref. 81198). Gut contents of four specimens include insect larvae, winged insects and plant matter (Ref. 81198).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Lima, F.C.T., W.B. Wosiacki and C.S. Ramos, 2009. Hemigrammus arua, a new species of characid (Characiformes: Characidae) from the lower Amazon, Brazil. Neotrop. Ichthyol. 7(2):153-160. (Ref. 81198)
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
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.02239 (0.00856 - 0.05854), b=3.00 (2.77 - 3.23), based on LWR estimates for this Subfamily-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.0 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months ().
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .