Lista sistemática de la ictiofauna en la Reserva de la Biosfera La Encrucijada, Chiapas, México

We provided a systematic checklist of fishes recorded on La Encrucijada Biosphere Reserve (REBIEN), during the period from 2004 to 2009. The systematic list is composed by 153 species that are included in 2 classes, 20 orders, 52 families and 107 genera. Nine species are added to the known continental environments of the state of Chiapas, 4 of them are registered by first time in estuarine-lagoon biotopes of México: Cathorops cf. fuerthii, Trichiurus nitens, Guavina micropus and Gobionellus liolepis, the last 2 species are reported for the first time in the Mexican pacific; the presence of the exotic cichlid Oreochromis niloticus is also reported. The best represented families in species richness were Carangidae (14), Sciaenidae (11), Gobiidae (10) and Ariidae (9). Based on its ecogeographical derivation, 4 species (2.6% ) are freshwater primary; 13 (8.5%) freshwater secondary, and 134 (88.9%) peripheral; the last group is ecologically composed by 3 catadromous species (2%), 11 estuarine residents (7.2%), 56 marine euryhalines (36.6%) and 66 marine stenohalines (43.1%). Biogeographically, 91.2% of the species are distributed in Eastern Pacific, 47.7% are from the Californian province, 65.4% from Cortés province, 80.4% from Panamian province, and 41.2% from Peruvian province. Comparatively, the REBIEN contains the highest fish richness in all the estuarine-lagoon systems along the Mexican Pacific.