UC San Diego

The perciform suborder Blennioidei comprises six families, 151 genera and 883 species. In Chapter 1, I analyzed the phylogenetic relationships of 160 blennioids and ten gobiesocids as the outgroup with one mitochondrial and four nuclear DNA markers. According to the consensus of Bayesian, Maximum Likelihood, and Maximum Parsimony analyses, the monophylies of the six families are supported except for the Labrisomidae and Chaenopsidae. The globally distributed families Tripterygiidae and Blenniidae, are the basal clades branched out of the blennioids. Relationships of the remaining families are partially resolved with the two temperate lineages, the tribe Cryptotremini (Labrisomidae) and the family Clinidae, positioned at the base. Our data suggest that the three Labrisomus subgenera Brockius, Gobioclinus, and Labrisomus should be recognized as separate genera. The recent expansion of the Chaenopsidae with the inclusion of Neoclinus, Mccoskerichthys, and Stathmonotus is not supported. Relationships of the mostly New World family Chaenopsidae are further investigated with additional 145 morphological characters in Chapter 2. The phylogeny based on the combined molecular and morphological dataset supports the monophyly of the subfamily Chaenopsinae and all included genera, but partially agrees with the formerly hypothesized inter-generic relationships based on morphology. Four major clades were identified. The genus Coralliozetus is sister to the remaining three clades which have unresolved relationships. Chaenopsids show higher-than-average genetic variation, therefore are ideal models for studying evolutionary mechanisms. In Chapter 3, a Gulf of California endemic chaenopsid Acanthemblemaria crockeri is shown to have a species-level divergence with subsequent differentiation based on two mitochondrial markers (COI and d-loop). The geographical boundary between the northern "Gulf" and southern "Cape" species roughly corresponds to a hypothetical Pliocene seaway north of the La Paz. Surprisingly, this pattern is not congruent with the well-recognized northern melanic and southern red color morphs. Another speciation event is confirmed from the A. hancocki species group. In Chapter 4, two mitochondrial and one nuclear intron markers were used to discover a new species endemic to the Gulf of California. Acanthemblemaria hastingsi sp. nov. is separated from its sister species A. macrospilus, by the Sinaloan Gap and differ in head and dorsal-fin color pattern