Rhamdia reddelli

Miller 1984

Rhamdia reddelli
Redrawn by Rhian Kendall from Miller (1984)






Holotype: UMMZ 211164 male (?) 98.5mm SL. Paratypes: UMMZ 199016 2 specimens 39mm and 70mm SL; UMMZ 211165 6 specimens 51.5mm‑94.2mm SL; UMMZ 211166 77.1mm SL; AMNH 38216 98.2mm SL; AMNH 38217 4 specimens 36.7mm ‑ 90.5mm SL; AMNH 38218 2 specimens 68.9mm and 69.5mm SL.


Type locality: Cueva del Nacimiento del Rio San Antonio, c. 9 km south‑west of Actalan, Oaxaca, on the Atlantic slope of eastern México (18oN, 97oW). Also recorded from Cueva de Maravillas in the same area where it co‑exists with an undescribed species, Rhamdia undescribed 1 (Mosier 1984 and see Elliott 2020 for details and surveys of these caves and two others).


Cueva del Nacimiento del Rio San Antonio contains a stream running over a substrate of sand and gravel with some areas of bedrock and flowstone. The fishes usually occur in the deeper, ponded sections of the stream, especially in areas over which bats roost. A rich invertebrate fauna is present in the cave and presumably provides the food supply for the fishes. It is not known if R. reddelli is also found in the deeper cave lake occupied by Rhamdia undescribed species 1 (Mosier 1984)


Silfvergrip (1996) considers Rhamdia reddelli to be a synonym of Rhamdia laticauda.

Arroyave and De La Cruz-Fernandez (2021) studied all four Mexican troglobitic Rhamdia (R. reddelli, R. zongolicensis, R. macuspanensis and R. laluchensis) with both genetics and morphology. They discovered that all four species are probably populations of the epigean Rhamdia laticauda but they refrained from making nomenclatural decisions, and thus placing all four as troglobitic populations of R. laticauda, until further data become available. The four species thus retain their current names for the timebeing (August 2021).

Conservation Status


Arroyave, J. 2019. Rhamdia reddelli. The IUCN Red List of Threatened Species 2019: e.T19455A2349297. Downloaded on 04 February 2021.

VU C2b,D2:2.3:1996

(Contreras-Balderas, S. & Almada-Villela, P. 1996. Rhamdia reddelli. The IUCN Red List of Threatened Species 1996: Downloaded on 14 July 2017).

V (IUCN 1990), V (IUCN 1993), Threatened (Contreras-Balderas, Almada-Villela, Lozano-Vilano and Garcia-Ramirez 2003).

Museum Holdings

As above only.

Key References

Reddell, J. R. Book 1981 A review of the cavernicole fauna of Mexico, Guatemala and Belize
LeGrande, W. H. Journal Article 1981 Chromosomal evolution in North American catfishes (Siluriformes, Ictaluridae) with particular emphasis on the Madtoms, Noturus
Miller, R. R. Journal Article 1984 Rhamdia reddelli, new species, the first blind pimelodid catfish from Middle America, with a key to Mexican species
Mosier, D. Journal Article 1984 Cave dwelling populations of Rhamdia (Pimelodidae)
Wilkens, H. Journal Article 1991 Comparative study and phylogenetic age of epigean and cave forms of the genus Rhamdia (Pimelodidae, Teleostei)
Wilkens, H., Junge, P. and Langecker, T. G. Journal Article 1991 Speciation of troglobites: Studies on the San Antonio Cave (Oaxaca, Mexico)
Anderßon, O. Thesis 1992 Vergleichende Untersuchung der Augenentwicklung der oberirdischen und der Höhlenformen der Gattung Rhamdia (Pimelodidae, Pisces)
Langecker, T.G. and Wilkens, H. Journal Article 1992 Comparative ultrastructural studies on the pineal organ of the Mexican catfish Rhamdia laticauda Heckel, 1858 and one of its cave-dwelling derivatives (Pimelodidae, Teleostei)
Junge, P. Journal Article 1992 Egg size and larval development of epigean and cave forms of Rhamdia guatemalensis (Pimelodidae, Pisces)
Wilkens, H. Journal Article 1993 A new species of Rhamdia (Pisces, Pimelodidae) from a cave in the Sierra de Zongolica (Veracruz, Mexico)
Wilkens, H. Journal Article 1993 Adaptation and phylogenetic age of Mexican epigean and cave Rhamdia (Pimelodidae)
Weber, A. Journal Article 1995 The lateral line system of epigean and cave dwelling catfishes of the genus Rhamdia (Pimelodidae, Teleostei) in Mexico
Weber, A. Journal Article 1996 Cave dwelling catfish populations of the genus Rhamdia (Pimelodidae, Siluroidei, Teleostei) in Mexico
Silfvergrip, A.M.C. Book 1996 A systematic revision of the neotropical catfish genus Rhamdia (Teleostei, Pimelodidae)
Weber, A. Journal Article 1998 Mexican cave catfish of the genus Rhamdia (Pimelodidae): notes on adaptation and distribution
Wilkens, H. Journal Article 2001 Convergent adaptations to cave life in the Rhamdia laticauda catfish group (Pimelodidae, Teleostei)
Perdices, A., Bermingham, E., Montilla, A. and Doadrio, I. Journal Article 2002 Evolutionary history of the genus Rhamdia (Teleostei: Pimelodidae) in Central America
Contreras-Balderas, S, Almada-Villela, P, Lozano-Vilano, M de L and Garcia-Ramirez, ME Journal Article 2003 Freshwater fish at risk or extinct in Mexico
Weber, A Thesis 2003 Taxonomie und Artstatus hohlenbewohnender und oberirdischer Welse der Gattung Rhamdia (Pimelodidae, Teleostei) in Mexiko
Hulsey, C.D. and Lopez-Fernandez, H. Book Section 2011 Nuclear Central America
Palacios-Vargas, J.G., Juberthie, C. and Reddell, J. Book 2014-2015 Encyclopaedia Biospeologica Mexico
Ricci, J.M.B.,Martinez, E.R.M., Butzge, A.J., Doretto, L.B., Oliveira, M.A., Bombardelli, R.A., Bogerd, J. and Nóbrega, R.H. Journal Article 2018 Characterization of vasa homolog in a neotropical catfish, Jundiá (Rhamdia quelen): Molecular cloning and expression analysis during embryonic and larval development
Scaglione, M.C., Cerutti, R.D., Arfuso, F. and Piccione, G. Journal Article 2018 Light and dark rations and the photic entrainment of circadian locomotor activity patterns in the South American Silver Catfish (Rhamdia quelen, Quoy & Gaimard, 1824)
Koerber, S. and Reis, R.E. Journal Article 2019 The current situation of Rhamdia Bleeker, 1858 (Siluriformes: Heptapteridae) – Gather available information, define a zero point, and start all over again
Warren, M.L. and Burr, B.M. Book 2020 Freshwater fishes of North America. Volume 2 Characidae to Poeciliidae
Thomas, M.R. and Sabaj, M.H. Book Section 2020 Heptapteridae: Seven-finned catfishes
Elliott, W.R. Journal Article 2020 The catfish caves of Acatlan, Oaxaca
Koerber, S. and Reis, R.E. Journal Article 2020 Evidence for the true type-locality of Rhamdia quelen (Siluriformes: Heptapteridae), and the geographical origin and invalid neotype designation of four of its synonyms
Arroyave, J. and De La Cruz Fernández, D.A. Journal Article 2021 Genetic and morphological evidence cast doubt on the validity of Mexican troglobitic species of the Neotropical catfish genus Rhamdia (Siluriformes: Heptapteridae).