Meeting Abstract

30.10  Friday, Jan. 4  Time-scale of spiny-rayed fish (Acanthomorpha, Teleostei). SANTINI, F.*; CARNEVALE, G.; ALFARO, M.A.; University of Toronto; University of Pisa; Washington State University francesco.santini@utoronto.ca

With approximately 18000 described species, spiny-rayed fishes (Acanthomorpha) constitute one of the most diverse and successful vertebrate clades. Most fish “model organisms” used in studies of genomics, developmental biology and population biology, including pufferfish, sticklebacks, ricefish, cichlids and guppies fall into this group. Although the fossil record of acanthomorphs is poorly known relative to some other teleost lineages, such as osteoglossomorphs and elopomorphs, a large number of fossils exist that can be assigned to stem or crown groups within the clade. Here we present the first chronogram for the Acanthomorpha that incorporates over 15 fossil calibrations, 130 taxa, and sequence data from both nuclear and mitochondrial genes (Rag1, Rhodopsin, Mll, 28S, 12S/16S). Although all major lineages that have been assigned ordinal status originate in the Late Cretaceous, the bulk of the acanthomorph radiation appears to have occurred after the KT extinction, between the early Paleocene and the early Eocene. We will use this calibrated phylogeny to discuss hypotheses concerning the origin, radiation, and diversification of several major acanthomorph clades.