DOI: 10.5061/dryad.s1rn8pkfx
title: Data from: Cretaceous amber inclusions illuminate the evolutionary origin of tardigrades

description: Supplementary files to the "Cretaceous amber inclusions illuminate
 the evolutionary origin of tardigrades" paper which include All raw
 files from the phylogenetic analysis (i.e., t, p, and tree files
 fromMrBayes, output tree from ASTRAL and IQTree, mcmc files from MCMCTree,
 and tre and log files from BEAST), RScripts used, and assembled
 Actinarctus doryphorus genome. Tardigrades are a diverse phylum of
 microscopic invertebrates widely known for their extreme survival
 capabilities. Molecular clocks suggest that tardigrades diverged from
 other panarthropods before the Cambrian, but their fossil record is
 extremely sparse. Only the fossil tardigrades Milnesium
 swolenskyi (Late Cretaceous) and Paradoryphoribius
 chronocaribbeus (Miocene) have resolved taxonomic positions,
 restricting the availability of calibration points for estimating for the
 origin of this phylum. Here, we revise two crown-group tardigrades from
 Canadian Cretaceous-aged amber using confocal fluorescence microscopy,
 revealing critical morphological characters that resolve their taxonomic
 positions. Formal morphological redescription of Beorn
 leggi reveals that it features Hypsibius-type claws. We
 also describe Aerobius dactylus gen. et sp. nov. based
 on its unique combination of claw characters. Phylogenetic
 analyses indicate that Beo. leggi and Aer.
 dactylus belong to the eutardigrade superfamily Hypsibioidea,
 adding a critical fossil calibration point to investigate tardigrade
 origins. Our molecular clock estimates suggest an early Paleozoic
 diversification of crown-group Tardigrada and highlight the importance
 of Beo. leggi as a calibration point that directly impacts
 estimates of shallow nodes. Our results suggest that independent
 terrestrialization of eutardigrades and heterotardigrades occurred around
 the end-Carboniferous and Lower Jurassic, respectively. These estimates
 also provide minimum ages for convergent acquisition of cryptobiosis.
description: # Data from: Cretaceous amber inclusions illuminate the evolutionary
 origin of tardigrades
 [https://doi.org/10.5061/dryad.s1rn8pkfx](https://doi.org/10.5061/dryad.s1rn8pkfx) * Raw S1 - t and p files from MrBayes - total-evidence phylogenetic analysis * Raw S2 - trees and mcmc_files from MCMCTree - phylogenomic dataset for divergence time estimation analysis - subfolders correspond to the different fossil calibration strategies as stated in the manuscript * Raw S3 - t and p files from MrBayes - 18S/28S rRNA dataset for divergence time estimation analysis * Raw S4 - log, trees, and consensus tree files from BEAST - 18S/28S rRNA dataset for divergence time estimation analysis - subfolders correspond to the different fossil calibration strategies as stated in the manuscript * Raw S5 - Rscripts used for making the density plots, error bar graphs, and chi-square analyses (see README.txt within this compressed folder for more details) * Raw S6 - Assembled *Actinarctus doryphorus* genome * Raw S7 - Output tree from ASTRAL - phylogenomic dataset for divergence time estimation analysis * Raw S8 - Output tree from IQTree - 18S/28S rRNA dataset for divergence time estimation analysis * Raw S9 - Output tree from MrBayes - 18S/28S rRNA dataset for divergence time estimation analysis