Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopteri (ray-finned fishes) > Siluriformes
(Catfish) > Doradidae
(Thorny catfishes) > Doradinae
Etymology: Hassar: Origin of the name was not specified by the author, but it is possible that it refers to the name commonly applied to certain catfishes in Guyana, such as Hoplosternum littorale or Hypostomus watawata.; shewellkeimi: Named for Mr. Shewell 'Bud' DeBenneville Keim, a nephew of Henry W. Fowler, who was the first full-time curator of fishes at the Academyof Natural Sciences from 1902-1965, for his generous support to Academy ichthyology, including the preservation of Fowler's legacy and the stewardships of his uncle's fishes.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal. Tropical
South America: rio Teles Pires and one or more sites in the upper rio Juruena in Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 22.1 cm SL male/unsexed; (Ref. 93284)
Morphology | Morphometrics
soft rays: 12 - 15. This species differs from other species of Hassar by its relatively narrow interorbital and long snout, interorbital width 32.2-44.7% distance from snout tip to anterior naris (vs. 45.0-89.4%). It is most similar to H. orestis, but it can be further separated from that species by having gas bladder with few, weakly developed peripheral diverticula restricted to anterolateral shoulder and posterolateral face of anterior chamber, and sometimes anterolateral face of posterior chamber (vs. well developed diverticula with multiple branches and grouped into fascicles encircling horizontal periphery of gas bladder in H. orestis), and posterior face of gas bladder smooth, broadly to narrowly rounded (vs. posterior chambers expanded posteriorly into medially conjoined ternimal diverticula, effecting acutely subtriangular, cone-shaped posterior face). This species also differs from H. affinis and H. gabiru by its snout, distance snout tip to anterior naris 9.5-12% SL (vs. 6.9-9.7% SL), interorbital width 3.4-4.8% SL and 9.8-14.7% HL (5.9-8.0% SL and 17.3-24.3% HL), and caudal peduncle depth 4.8-5.6% SL (vs. 6.6-8.0% SL). It is diagnosed from all congeners except H. orestis by the distal half of soft dorsal fin consisting of distinct dark subtriangular blotch not extending to distal margin, pale margin complete, its width approaching that of blotch (vs. distal half of soft dorsal dfn dusky to margin in H. affinis; or with dark blotch leaving narrow pale distal margin, width less than half that of dark blotch, in H. gabiru, H. wilderi and sometimes H. orestis) (Ref. 93284).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Sabaj Pérez, M.H. and J.L.O. Birindelli, 2013. Hassar shewellkeimi, a new species of thorny catfish (Siluriformes: Doradidae) from the upper Tapajós basin, Brazil. Proc. Acad. Nat. Sci. Philadelphia 162:133-156. (Ref. 93284)
IUCN Red List Status (Ref. 123251)
CITES (Ref. 123416)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.5312 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00813 (0.00356 - 0.01856), 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
): 2.8 ±0.4 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (27 of 100) .