Abstract
A new species of freshwater crab of the family Trichodactylidae, genus Rodriguezia Bott, 1969 is described from Grutas de Agua Blanca in southern Tabasco, Mexico. Rodriguezia is a genus endemic to northern Chiapas and southern Tabasco, distributed over a small area of 70 km. Rodriguezia adani n. sp., the third species of the genus, occurs north of its two congeners, being stygobitic with obvious adaptations to cave life. It can be distinguished from R. villalobosi, an epigean species, by the absence of eyes, lack of pigmentation and elongation of the pereiopods; and from R. mensabak by having less elongated pereiopods relative to carapace breadth, an extremely reduced ocular peduncle, and a smaller adult size.
References
Bott, R. (1969) Die Süsswasserkrabben Süd-Amerikas und ihre Stammesgeschichte. Eine Revision der Trichodactylidae und der Pseudothelphusidae östlich der Anden (Crustacea, Decapoda). Abhandlungen der Senckenbergischen Naturforschenden Gesellschaft (Frankfurt am Main), 518, 1–94.
Cottarelli, V. & Argano, R. (1977) Trichodactylus (Rodriguezia) mensabak n. sp. (Crustacea, Decapoda, Brachyura), granchio cieco delle acque sotterranee del Chiapas (Messico). Quaderni Problemi Attuali di Scienza e di Cultura, Accademia Nazionale dei Lincei, 171, 207–212.
Ecosur (2001) Geological map of Chiapas, Mexico (1:2,000,000). El Colegio de la Frontera Sur - INEGI. Available from: www.ecosur.mx/sitios/images/stories/ecosur/Servicios/LAIGE/mapas_PEOT/glmp_geologia.jpg (accessed 8 August 2018)
Magalhães, C. & Türkay, M. (2012) Taxonomy of the Neotropical freshwater crab family Trichodactylidae. VI: The genera Avotrichodactylus and Rodriguezia (Decapoda: Brachyura: Trichodactylidae). Nauplius, 20, 27–40.
https://doi.org/10.1590/S0104-64972012000100004Ojeda, J.C., Alvarez, F. & Villalobos, J.L. (2013) Revisión de los cangrejos de agua dulce de la familia Trichodactylidae de México. In: López-Mejía, M. & Mejía-Ortíz, L.M. (Eds.), La Carcinología en México. Universidad de Quintana Roo, Chetumal, Quintana Roo, pp. 23–36.
Rodríguez, G. (1992) The freshwater crabs of America. Faune Tropicale, 31, 1–189.
Rodríguez, G. & Manrique, F. (1967) El género Trichodactylus en México (Brachyura, Potamonidae). Anales del Instituto de Biología, 37, 183–185.
Weber, A. & Wilkens, H. (1998) Rhamdia macuspanensis: A new species of troglobitic pimelodid catfish (Siluriformes; Pimelodidae) from a cave in Tabasco, Mexico. Copeia, 1998 (4), 998–1004.
https://doi.org/10.2307/1447347