Conidae phylogenomics and evolution

Abstract

[EN] Understanding the relative role of different evolutionary processes leading to the extraordinary morphological, ecological and species diversity of cone snails requires a robust phylogeny, which thus far has been elusive. Here, we constructed a mitochondrial (mt) genome data set, which included four newly sequenced mt genomes, 25 publicly available mt genomes and 24 data sets with all mt protein¿coding and rRNA genes assembled from venom gland transcriptomes. In total, we analysed 42 different species representing 27 genera of cone snails, that is, about one third of the generic diversity of the group. In addition, we used the RNA¿Seq reads to assemble 21 nuclear genes, which were concatenated in a nuclear data set. Finally, a combined data set including mt and nuclear genes was also constructed. The three data matrices were analysed with probabilistic methods, site¿homogeneous and site¿heterogeneous models, and with protein¿coding genes both at the amino acid and nucleotide levels. Diet specialization, radular morphology and the type of protoconch (paucispiral or multispiral indicating lecithotrophic or planktonic larvae, respectively) as well as conotoxin diversity were mapped onto the reconstructed mt phylogeny, and a chronogram dating mayor cladogenetic events within the group was also reconstructed.