Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Cyprinodontiformes
(Rivulines, killifishes and live bearers) > Rivulidae
Etymology: gracilis: The specific name gracilis (tenuous, small) is in reference to the small size of this psecies, the largest recorded specimen reaching about half the length of its congeners.. More on author: Costa.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; benthopelagic. Tropical
South America: Mato Grosso River drainage, Saquarema Lagoon basin in southeastern Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 2.8 cm SL male/unsexed; (Ref. 72398)
Morphology | Morphometrics
soft rays: 12 - 13;
Vertebrae: 31. Anal fin with 11-13 rays; scales on the longitudinal series 29-30; caudal fin acuminate in males; mandibular neuromasts 4 +2; jaw length 19.5-23.5% of HL; dorsal portion of pectoral-fin base with dark grey spot; flank dark brown with horizontal rows of greenish blue spots on anterior portion and metallic blue bars on posterior portion in males, dark brown stripe on isthmus in males, dark brown and white alternating short bars on basal portion of anal fin in males and horizontal rows of pale golden to pale blue spots on flank in females (Ref. 72398).
Found in creeks and swamps in open vegetation areas, in shallow water (about 5-10 cm deep), both in clear and tea colored water (Ref. 72398). Feeds mainly on ostracods and terrestrial arthropods, but also takes copepods and decapods (Ref. 72398).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Costa, W.J.E.M., 2007. Kryptolebias gracilis n. sp. (Teleostei: Cyprinodontiformes: Rivulidae): a new killifish from the Saquarema Lagoon basin, southeastern Brazil. Aqua Int. J. Ichthyol. 13(1):7-12. (Ref. 72398)
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
= 0.5039 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01175 (0.00445 - 0.03100), b=3.04 (2.81 - 3.27), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.1 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 69278
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .