An updated taxonomic list of marine fish larvae from the Gulf of California to Colima, Mexico is presented. A total of 579 taxa belonging to 119 families, 256 genera, and 423 species were recorded. The list was compiled using 14 publications on fish larvae research (1974-2012), and the fish larvae identified from 315 samples collected with Bongo nets during 10 oceanographic cruises made from the Gulf of California to Bahía de Banderas, Mexico, from 2003 to 2007 (this study). The most important families in this study were the Myctophidae (28.3%), Engraulidae (25.0%), and Clupeidae (15.4%). The most abundant species were Cetengraulis mysticetus (18.2%), Benthosema panamense (13.9%), and Opisthonema libertate (12.7%). The compiled taxonomic list shows the addition of 296 new taxa to the previous list published 10 years ago, and also the need of an increase in the effort on the taxonomy of fish larvae forms not identified to species level.

ABSTRACT. Larval fish composition and abundance were analyzed during February-March (winter) and November-December (autumn) of 2005 to investigate which environmental conditions and mesoscale oceanographic processes affect the distribution of larval fish assemblages in the Gulf of California, and if these variables and processes are useful to delimit specific regions of ichthyofaunal distribution. The overall pattern was mostly a latitudinal gradient of the abundance of two faunistic complexes of larval fish assemblages (temperate northern and tropical southern complexes) strongly associated with the spatial distribution of sea surface temperature. The integration of these results, with previous investigations in the region, lets us confirm that the northern and southern larval fish assemblages extend and contract their distribution ranges according to the latitudinal displacement of the 21°C sea surface isotherm. We identified this to be a valuable criterion to establish the southern distribution limit of the temperate larval fish assemblage, and the 18°C as the northern limit of the tropical larval fish assemblage. However, this general pattern is maintained only in absence of mesoscale oceanographic features (upwelling and eddies) that increase larval drift from the coast to the central region of the Gulf, particularly during the November-December period when longitudinal gradients were stronger than in February-March.