02336nas a2200253   4500008004100000022001400041245010900055210006900164260001500233300001600248490000700264520155700271653001701828653001401845653001301859653001601872653001601888653001501904100002201919700003001941700003001971700002102001856006002022       2021                        eng d  a1537-171900aPhylogenomic Analysis of Velvet Worms (Onychophora) Uncovers an Evolutionary Radiation in the Neotropics0 aPhylogenomic Analysis of Velvet Worms Onychophora Uncovers an Ev  c24/08/2021  a5391 - 54040 v383 a<p>Onychophora (&ldquo;velvet worms&rdquo;) are charismatic soil invertebrates known for their status as a &ldquo;living fossil,&rdquo; their phylogenetic affiliation to arthropods, and their distinctive biogeographic patterns. However, several aspects of their internal phylogenetic relationships remain unresolved, limiting our understanding of the group&rsquo;s evolutionary history, particularly with regard to changes in reproductive mode and dispersal ability. To address these gaps, we used RNA sequencing and phylogenomic analysis of transcriptomes to reconstruct the evolutionary relationships and infer divergence times within the phylum. We recovered a fully resolved and well-supported phylogeny for the circum-Antarctic family Peripatopsidae, which retains signals of Gondwanan vicariance and showcases the evolutionary lability of reproductive mode in the family. Within the Neotropical clade of Peripatidae, though, we found that amino acid-translated sequence data masked nearly all phylogenetic signal, resulting in highly unstable and poorly supported relationships. Analyses using nucleotide sequence data were able to resolve many more relationships, though we still saw discordant phylogenetic signal between genes, probably indicative of a rapid, mid-Cretaceous radiation in the group. Finally, we hypothesize that the unique reproductive mode of placentotrophic viviparity found in all Neotropical peripatids may have facilitated the multiple inferred instances of over-water dispersal and establishment on oceanic islands.</p>
10abiogeography10adispersal10aGondwana10aOnychophora10asystematics10avicariance1 aBaker, Caitlin, M1 aBuckman-Young, Rebecca, S1 aCosta, Cristiano, Sampaio1 aGiribet, Gonzalo  uhttps://academic.oup.com/mbe/article/38/12/5391/6357048