Rhamdia zongolicensis

Wilkens 1993

Rhamdia zongolicensis
Redrawn by Rhian Kendall from Wilkens (1993)


Rhamdia zongolicensis was described as a new species by Wilkens (1993). In a review of all neotropical species of Rhamdia Silfvergrip (1996) did not accept that R. zongolicensis was a separate species and placed it in synonymy with R. laticauda. In a wide ranging study Arroyave and De La Cruz Fernandex (2021 and submitted) studied fishes from six caves in the Sierra de Zongolica (see below) and were of the opinion that all were cave-adapted species of R. laticauda rather than separate species, thus agreeing with Silfvergrip (1996). In the 2021 paper they decided  that these results were preliminary and retained R. zongolicensis, from its type locailty, as a separate species while including five other species as populations of R. laticauda. For the purposes of this species account we will retain all six population within R. zongolicensis (for simplicity) and await publication of their second, submitted,  paper which will provide the details necessary to write one or more species accounts for the six known populations.


Rhamdia laticauda  




Holotype: ZMH 8249 92mm SL. Paratypes: ZMH 8250, 3 specimens 65-85mm SL.


Type locality: Cueva del Ostoc, Sierra de Zongolica, Veracruz, México (18oN, 97oW). This cave is also known as Cueva de El Túnel and under this name was described by Robertson (1983a, 1983b) and Mosier (1984) both of whom mentioned the fishes, the former also providing a photograph. Arroyave and De La Cruz Fernandez (2021) found populations of fishes with varying degrees of troglomorphy in the following caves within the Sierra de Zongolica:

Population Lat. Long. Municipality Depth (m) Voucher specimens Degree of troglomorphy (1-5)
Cueva del Ostoc 18.61 -96.89 Zongolica 30 See below 2
Sumidero de Cotzalostoc 18.7 -96.92 Totolacatla 200 See below 4
Sotano de Popacatl 18.76 -96.95 Coetzala 74 See below 3
Sotano de Ahuihuitzcapa 18.73 -96.93 Totolacatla 455 See below -
Cueva Piedras Blancas 18.67 -96.9 Zongolica 5 See below 0
Cueva del Naranjal 18.78 -96.96 Naranjal 50-70 See below 1



There is little published information. Wilkens (1993a) reports that there was no other animal life in the pools in the cave and that the type specimens were undernourished. This may suggest that the food supply is episodic, perhaps related to flood events. Robertson (1983) provides a survey.


Silfvergrip (1986) does not accept that this species is diagnosable from Rhamdia laticauda and places it within that species.

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

[VU D2:3.1:2019]

Arroyave, J. and Schmitter-Soto, J. 2019. Rhamdia zongolicensis. The IUCN Red List of Threatened Species 2019: e.T19456A2349993. Downloaded on 10 December 2020.

Threatened (Contreras-Balderas et al. 2003)


1996 – Vulnerable (VU)

Museum Holdings

All from Arroyave and De la Cruz Fernandez (2021)

Cueva Ostoc ZMH 8249, THNC 11640, 11660, 23873, CNPE-IBUNAM 23800, 23806

Sumidero de Cotzalostoc THNC 11642, CNPE-IBUNAM 23799

Sótano de Popocatl THNC 11641, 11661, CNPE-IBUNAM 23802, 23816, 23817

Sótano de Ahuihuitzcapa THNC 11662

Cueva Piedras Blancas CNPE-IBUNAM 23801

Cueva del Naranjal CNPE-IBUNAM 23803

Key References

Robertson, S. Journal Article 1983 Zongolica project
Robertson, S. Journal Article 1983 Cueva del Tunel, Veracruz
Mosier, D. Journal Article 1984 Cave dwelling populations of Rhamdia (Pimelodidae)
Williams, J.E., Johnson, J.E., Hendrickson, D.A., Conteras-Balderas, S., Williams, J.D., Navarro-Mondoza, M., McAllister, D.E. and Deacon, J.E. Journal Article 1989 Fishes of North America endangered, threatened or of special concern 1989
Wilkens, H. Journal Article 1991 Comparative study and phylogenetic age of epigean and cave forms of the genus Rhamdia (Pimelodidae, Teleostei)
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
Weber, A Thesis 2003 Taxonomie und Artstatus hohlenbewohnender und oberirdischer Welse der Gattung Rhamdia (Pimelodidae, Teleostei) in Mexiko
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
Contreras-Balderas, S and others, 13 Journal Article 2008 Freshwater fishes and water status in México: A country-wide appraisal
Hulsey, C.D. and Lopez-Fernandez, H. Book Section 2011 Nuclear Central America
Contreras-Macbeath, T., Rodriguez, M.B., Sorani, V., Goldspink, C., and McGregor Reid, G. Journal Article 2014 Richness and endemism of the freshwater fishes of Mexico
Palacios-Vargas, J.G., Juberthie, C. and Reddell, J. Book 2014-2015 Encyclopaedia Biospeologica Mexico
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
Thomas, M.R. and Sabaj, M.H. Book Section 2020 Heptapteridae: Seven-finned catfishes
Lyons, T.J., Máiz-Tomé, L., Tognelli, M., Daniels, A., Meredith, C., Bullock, R. and Harrison, I., Contreras-MacBeath, T., Hendrickson, D.A., Arroyave, J., Mercado Silva, N., Köck, M., Domínguez Domínguez, O., Valdés González, A., Espinosa Pérez et al. Book 2020 The status and distribution of freshwater fishes in Mexico
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
Warren, M.L. and Burr, B.M. Book 2020 Freshwater fishes of North America. Volume 2 Characidae to Poeciliidae
Arroyave, J. and De La Cruz Fernández, D.A. Journal Article 2021 Cave-dwelling populations of Rhamdia (Siluriformes: Heptapteridae) from the Sierra de Zongolica, Veracruz, Mexico: an evidence-based checklist with comments on their evolutionary history and taxonomy
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).