Classification / Names
Common names | Synonyms | Catalog of Fishes (gen., sp.) | ITIS | CoL | WoRMS | Cloffa
Actinopterygii (ray-finned fishes) > Siluriformes
(Catfish) > Heptapteridae
Etymology: Rhamdiopsis: Brazilian vernacular name, Nhamdia/Jamdia (Ref. 45335); krugi: Named for Luiz Krug, professional tourist guide based in the city of Lençóis, in the Chapada Diamantina area, who called our attention of the existence of this new catfish and helped to collect its type series, and for his efforts dedicated to its
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal. Tropical
South America: lake inside the Poço Encantado cave, and isolated pools inside the Lapa do Bode and Natal caves in Bahia, Brazil.
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 3.7 cm SL male/unsexed; (Ref. 86271)
Morphology | Morphometrics
soft rays: 13 - 17. Distinguished from its congeners, Rhamdiopsis microcephala and Rhamdiopsis moreirai by the possession of the following characters: ethmoid cartilage discontinuous; eyes absent and optic foramen atrophied; longer barbels, length of maxillary barbel 32.2-43.3% SL; supraorbital and infraorbital sensory canals not connected to each other anteriorly; presence of s7 branch and pore of the supraorbital laterosensory canal; no subpreopercle; anterior and posterior branches of the transverse process 4 co-ossified to each other; posterior limb of transverse process 4 undivided, with spatulated shape; posterolateral corner of posterior portion of the posterior branch of the transverse process of vertebra 4 extending approximately to midlength of the transverse process of vertebra 5; presence of a widely exposed pseudotympanum; dorsal fin larger, dorsal-fin base 11.2-14.1% SL and length of third dorsal-fin ray 14.4-18.7% SL; posterior lobe of the adipose fin straight; anal fin deep and rounded; shorter anal-fin base, supported typically by 14-15, less commonly 13 or 16-17 rays; hypural 5 usually co-ossified to hypural 4 at its distal portion; dorsal hypural plate typically with 7, rarely 6 or 8 rays; dorsal caudal-fin lobe typically with 6, rarely 4, 5 or 7 branched rays; ventral caudal plate typically with 6, rarely 7 rays; ventral
caudal-fin lobe typically with 6, rarely 4 or 5 branched rays; body relatively shorter, with 38-40 vertebrae; lateral line very short, with 5-15 pores, usually reaching from the vertical through posterior region of pseudotympanum to the vertical through dorsal-fin origin; fatty tissue
broadly spread through the body; adults of small body size, reaching 3.85 cm SL; body unpigmented; non-cryptobiotic behavior, expressed by marked midwater activity; non-photophobic behavior; poorly-developed circadian rhythms; and life in lentic habitat. Differs also from Rhamdiopsis microcephala by its epiphyseal branches of supraorbital laterosensory canals not fused to each other, each one bearing its own pore, the s6 pore, and basal third of the posterior border of the adipose fin connected with the dorsal fold of caudal fin, leaving a large, almost complete free posterior lobe (Ref. 86271).
Found in the upper phreatic zone of a large karstic area (over 300 km2) including limestones
and quartzites, which is connected to surface through caves. Inhabits lentic waters formed by the water table inside the caves, varying from large, partially illuminated lakes to isolated pools. Mainly solitary. Observed swimming up to about 35 m depth, but it usually aggregates between the surface and 10 m. Reported to show preference for substrate, concentrating in the rocky walls. Strictly a carnivorous species which feeds on invertebrates found near or on the bat guano (Ref. 86271).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Bockmann, F.A. and R.M.C. Castro, 2010. The blind catfish from the caves of Chapada Diamantina, Bahia, Brazil (Siluriformes: Heptapteridae): description, anatomy, phylogenetic relationships, natural history, and biogeography. Neotrop. Ichthyol. 8(4):673-706. (Ref. 86271)
IUCN Red List Status (Ref. 120744)
CITES (Ref. 118484)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.6250 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00813 (0.00351 - 0.01882), b=3.01 (2.81 - 3.21), in cm Total Length, based on LWR estimates for this (Sub)family-body shape (Ref. 93245
Trophic Level (Ref. 69278
): 3.2 ±0.4 se; Based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months ().
Vulnerability (Ref. 59153
): Low vulnerability (10 of 100) .