Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Siluriformes
(Catfish) > Loricariidae
(Armored catfishes) > Hypoptopomatinae
Etymology: anosteos: From the Greek Gymnos, naked, and Otocinclus, a genus of the Hypoptopomatinae, in allusion to the extreme
reduction of the body encasing dermal plates. From the Greek anosteos, meaning boneless, in allusion to the absence of the late.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical; 14°S - 15°S, 47°W - 48°W
South America: Brazil. Known only from two creeks, both tributaries to the rio Tocantinzinho, in the headwaters of the rio Tocantins basin, Goiás (Ref. 79020).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 4.4 cm SL male/unsexed; (Ref. 79020)
Morphology | Morphometrics
Gymnotocinclus is distinguished from all other hypoptopomatine genera by the following uniquely derived features: extreme reduction of body dermal plates; absence of the lateral connecting bone; absence of bifid hemal spines on the abdominal vertebrae posterior to the first anal-fin proximal radial; and odontode tips
on last dermal plates on the caudal peduncle dorsally or anteriorly curved. Gymnotocinclus is also distinguished
by a number of non-exclusive traits: maxillary barbel adnateto the lower lip; lateral ethmoid almost completely encapsulating the nasal organ; ventral margin of preopercle straight, not deflected medially; pectoral girdle exposed and
supporting odontodes only in a restricted lateral area near base of pectoral fin; and absence of a pectoral-fin slit (Ref. 79020).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Carvalho, T.P., P. Lehmann A. and R.E. Reis, 2008. Gymnotocinclus anosteos, a new uniquely-plated genus and species of loricariid catfish (Teleostei: Siluriformes) from the upper rio Tocantins basin, central Brazil. Neotrop. Ichthyol. 6(3):329-338. (Ref. 79020)
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
= 1.0000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00550 (0.00225 - 0.01343), b=3.11 (2.90 - 3.32), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 2.1 ±0.1 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) .