Composition and zoogeography of fishes in Mangrove ecosystems of Baja California Sur, México

An updated systematic and zoogeographical checklist of fishes associated to mangrove estuaries of Baja California Sur (BCS) is provided in the present chapter. This checklist is based on records of literature and of verified voucher specimens from museums. Fish diversity from mangrove estuaries of BCS is composed by 228 species, 147 genera, 72 families, 23 orders, and two classes. Fish fauna of BCS is dominated by the class Actinopterygii (208 spp.) and the order Perciformes (125 spp.) with four families (Haemulidae, Sciaenidae, Gobiidae and Carangidae) representing more than 50% of the fish species into the order. Biogeographically, the ichthyofauna showed a mixture of species from derivation of temperate and tropical regions, with high affinities to the Cortez province (83.7%) followed by Mexican (73%) and Panamic (70.3%) provinces; however, more than 61.2% of the species extend their geographic ranges into the San Diegan province. Other species (6.6%) have circumtropical (13 spp.), amphiamerican (1 sp.) and amphipacific (1 sp.) affinities; and four species are from exotic origin (Poecilia butleri, P. reticulata, Sparus aurata, and Tilapia cf. zillii). Three taxa endemic to the Gulf of California were also recorded (Aruma histrio, Barbulifer pantherinus and Gobiosoma chiquita). Bahía de la Paz (62.7%) and Bahía Magdalena (55.7%) were the most extensive mangrove ecosystems in BCS, both contributing with the highest number of species. High fish diversity reported here, reflects the important role of the mangrove estuary ecosystems as primary habitat or nursery (feeding and spawning) for many marine species, contributing with the growth, recruitment and conservation of species with commercial or ecological value.