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: Hyphessobrycon: Greek, hyphesson, -on, -on = a little smaller + Greek, bryko = to bite (Ref. 45335); kayabi: Named for the the Kayabi Indians, a Tupi-speaking Indian nation, who, after suffering severe onslaughts from the western/Brazilian society during the first half of the 20th Century, still survive as a small group in a recently established area at the lower Rio Teles Pires, but mostly as a transplanted population at the Xingu Indigenous Park.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical
South America: Rio Teles Pires, Rio Tapajós basin in Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 2.8 cm SL male/unsexed; (Ref. 94770)
Morphology | Morphometrics
soft rays: 21 - 24. Hyphessobrycon kayabi can be diagnosed from all its congeners, except for H. bifasciatus, H. cyanotaenia, H. heliacus, H. igneus, H. loweae and H. peugeoti by having distal border of the anal fin slightly convex to straight, without a distinct anterior lobe in adult males, with last unbranched ray and first to second branched ray shorter than the subsequent branched rays (vs. distinct anterior lobe present in most congeners, with last unbranched ray and first and second branched rays longer than remaining rays). It differs from H. bifasciatus, H. cyanotaenia, H. heliacus, H. igneus, H. loweae, and H. peugeoti by having octa- to decacuspid inner premaxillary teeth (vs. tetra- to pentacuspid in H. bifasciatus and H. igneus, heptacuspid in H. heliacus, penta- to heptacuspid in H. cyanotaenia and H. loweae, and hexa- to heptacuspid in H. peugeoti), and by having dark chromatophores concentrated on the posterior border of the body scales, forming a reticulated color pattern (vs. reticulated pattern absent). It can be separated from Hyphessobrycon heliacus, H. loweae, and H. peugeoti by the absence of an elongated, filamentous dorsal fin in adult males (vs. elongated, filamentous dorsal fin present in adult males). It further differs from H. bifasciatus by having a single humeral blotch (vs. two well-defined humeral blotches) and from H. bifasciatus and H. igneus by having 17-20 branched anal-fin rays (vs. 27-32 in H. bifasciatus, and 23-29 in H. igneus) and by the absence of hooks on anal fin in mature males (vs. presence in H.bifasciatus and H. igneus) (Ref. 94770).
The type locality, Lagoa Azul, a terra-firme lake near the margin of the Rio Teles Pires, connected to it, with crystal-clear water, fed by springs at the bottom of the lake, and large stands of
subaquatic macrophytes. Stomach content analysis based on three specimens reveals that this species feeds mostly on vegetal matter (macrophyte fragments, unicellular and filamentous algae), and a smaller proportion of other organisms (testate amoebae, Cladocera, aquatic Hemiptera, Chironomidae larvae, unidentified invertebrate eggs). Observed during snorkeling sessions to browse on the periphyton growing on the surface of large submerged macrophytes leaves (Nymphaeaceae). Occurs syntopically at Lagoa Azul with other characids including Thayeria sp., Hemigrammus sp., Moenkhausia ceros, M. cotinho, M. colletti, and M. cf. lepidura, as well as several cichlids, anostomids, poeciliids, and stingrays (Ref. 94770).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Teixeira, T.F., F.C.T. Lima and J. Zuanon, 2013. A new Hyphessobrycon Durbin from the Rio Teles Pires. Rio Tapajós basin, Mato Grosso State, Brazil. (Characiformes: Characidae). Copeia 2013(4):612-621. (Ref. 94770)
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=0.01445 (0.00650 - 0.03213), b=3.06 (2.87 - 3.25), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 2.9 ±0.3 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .