First global phylogeny of whip spiders (Amblypygi)
Creators: name: de Miranda, Gustavo
name: Kulkarni, Siddharth
name: Tagliatela, Jéssica
name: Baker, Caitlin M.
name: Giupponi, Alessandro P.L.
name: Labarque, Facundo
name: Gavish-Regev, Efrat
name: Rix, Michael
name: Carvalho, Leonardo S.
name: Fusari, Lívia Maria
name: Harvey, Mark
name: Wood, Hannah M.
name: Sharma, Prashant
Publisher: name: Zenodo
Year: 2024
Subjects: Phylogenomics
ultraconserved
molecular dating
concordance factor
extinction

description: Asymmetrical rates of cladogenesis and extinction abound in the Tree of Life, resulting in numerous minute clades that are dwarfed by larger sister groups. Such taxa are commonly regarded as phylogenetic relicts or "living fossils" when they exhibit an ancient first appearance in the fossil record and prolonged external morphological stasis, particularly in comparison to their more diversified sister groups. Due to their special status, various phylogenetic relicts tend to be well-studied and prioritized for conservation. A notable exception to this trend is found within Amblypygi ("whip spiders"), a visually striking order of functionally hexapodous arachnids that are notable for their antenniform first walking leg pair (the eponymous "whips"). Paleoamblypygi, the putative sister group to the remaining Amblypygi, is known from Late Carboniferous and Eocene deposits but is survived by a single living species, Paracharon caecus Hansen, 1921, that was last collected in 1899. Due to the absence of genomic sequence-grade tissue for this vital taxon, there is no global molecular phylogeny for Amblypygi to date, nor a fossil-calibrated estimation of divergences within the group. Here, we report several individuals of a previously unknown species of Paleoamblypygi from a cave site in Colombia. Capitalizing upon this discovery, we generated the first molecular phylogeny of Amblypygi, integrating ultraconserved element sequencing with legacy Sanger datasets and including described extant genera. To quantify the impact of sampling Paleoamblypygi on divergence time estimation, we performed in silico experiments with pruning of Paracharon. We demonstrate that the omission of relicts has a significant impact on the accuracy of node dating approaches that outweighs the impact of excluding ingroup fossils. Our results underscore the imperative for biodiversity discovery efforts in elucidating the phylogenetic relationships of "dark taxa", and especially phylogenetic relicts in tropical and subtropical habitats. The lack of reciprocal monophyly for Charontidae and Charinidae leads us to subsume them into one family, Charontidae (new synonymy).
description: Funding provided by: National Science FoundationCrossref Funder Registry ID: https://ror.org/021nxhr62Award Number: IOS-2016141
Funding provided by: Coordenação de Aperfeicoamento de Pessoal de Nível SuperiorCrossref Funder Registry ID: https://ror.org/00x0ma614Award Number: 88882.426372/2019-01
Funding provided by: United States-Israel Binational Science FoundationCrossref Funder Registry ID: https://ror.org/00j8z2m73Award Number: 2019216
Funding provided by: Coordenação de Aperfeicoamento de Pessoal de Nível SuperiorCrossref Funder Registry ID: https://ror.org/00x0ma614Award Number: 88887.631058/2021-00