A molecular tree of 412 named tardigrade species from all public 18S, 28S and COI, with the records it cannot accept

Tardigrada has 1,546 described extant species and no species-level molecular tree. We built one from every public 18S, 28S and COI sequence that can be matched to a name in the current checklist: 422 tips, of which 412 are named species, 27% of the phylum, against the 45th edition of the Degma checklist. Both classes, both eutardigrade orders and all four parachelan superfamilies are recovered as clades at maximal support, and the root on the class split is confirmed separately with eight outgroups. Every checklist taxon with two or more tips is tested automatically for monophyly. 27 are contradicted by a clade with ultrafast bootstrap ≥ 95, 24 of them also with SH-aLRT ≥ 80, and 11 are contradicted independently by two or three single-marker trees. Checked one by one against the revision literature, none of the 11 is new: seven reproduce published phylogenies the checklist has not absorbed, and four trace to single misidentified records or an alignment artefact that passed the independent-markers test only because every marker came from the same specimen — so marker independence is not specimen independence, and the grading has to use the second. A gap map identifies 8 families and 60 genera (115 described species) with no named public sequence, concentrated in the marine arthrotardigrades, whose families are sampled four to ten times worse than the limno-terrestrial ones. Carrying equal weight with the tree is the screen that produced it: 176 deposited records were excluded with written evidence, including a 2026 museum amplicon batch in which one Macrobiotus 18S appears under three species names across two classes, a 2012 phylum-level dataset with three Hypsibius convergens isolates carrying rDNA of three different genera, and 81 COI records filed under a name the depositing study itself reports as a species complex. The batch was reported to the depositing laboratory, who acknowledged it the same day. Everything here is one script and one command. Files: the preprint, and moltree-data.zip with the tree, alignments, IQ-TREE reports, the full record screen (every excluded record with its evidence), the conflict check, and the build script.