Too rough to be a Hypsibius: multipopulation survey accentuates the phylogenetic position and apomorphies of Hypsibius scabropygus (Eutardigrada: Hypsibiidae) Author Gąsiorek, Piotr Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark & Department of Invertebrate Evolution, Faculty of Biology, Jagiellonian University, Kraków, Poland piotr.lukas.gasiorek@gmail.com Author SØrensen, Martin V. Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark Author Lillemark, Marie Rathcke Natural History Museum of Denmark, University of Copenhagen, Copenhagen, Denmark Author TØttrup, Frederik LeerhØi Anders P. text Zoological Journal of the Linnean Society 2024 Zool. J. Linn. Soc. 2024-12-17 202 4 1 18 https://doi.org/10.1093/zoolinnean/zlae160 journal article 308008 10.1093/zoolinnean/zlae160 f442baa6-585d-4612-803f-32db5f2baa5d 0024-4082 14825615 Parahypsibius Gąsiorek gen. nov. urn:lsid:zoobank.org:act: 4516C76C-F0EB-443F-A809- C29EB43F38FB . Type species: Hypsibius scabropygus Cuénot, 1929 . Diagnosis: Hypsibiids with Ramazzottius -like claws and rigid buccal tube bent posteriorly. Only posterior bars may be present. AISMs asymmetrical, dorsal AISM shorter and higher than ventral, with prominent apex and less evident caudal processes. Pharynx with two granular macroplacoids. Rudimentary elliptical sensory organs present on head. Cuticular sculpturing well developed as protuberances at least in the dorsoposterior body portion, or protuberances cover an entire dorsum. Eggs laid within the exuviae, with granulated chorion. Etymology: From Greek para - = near, close + Hypsibius , referring to the close relationship between these genera. Composition: P. biscuitiformis ( Bartoš, 1960 ) comb. nov. ; P. calcaratus ( Bartoš, 1935 ) comb. nov. ; P. camelopardalis ( Ramazzotti and Maucci, 1983 ) comb. nov. ; P. macrocalcaratus Figure 4. Variability of cuticular sculpturing of Hypsibius species from the scabropygus group (PCM): A, frontal and middle body part; B, C, middle and caudal body part; D, caudal body part (all H. scabropygus , Denmark); E, caudal body part ( H . cf. camelopardalis , Italy); F, G, caudal body part ( H . sp. nov., Denmark). Scale bars are in µm. ( Beasley, 1988 ) comb. nov. ; P. ragonesei ( Binda and Pilato, 1985 ) comb. nov. ; P. roanensis ( Nelson and McGlothlin, 1993 ) comb. nov. ; P. scabropygus ( Cuénot, 1929 ) comb. nov. ; P. stiliferus ( Abe, 2004 ) comb. nov. ; and P. runae ( Bartoš, 1941 ) comb. nov. (uncertain, type specimens are unusable due to the crystallization of mounting medium, thus the transfer is done based on simplistic original description). Geographic distribution: Essentially Holarctic. Among all the species included in the genus, only H. scabropygus was recorded outside of the Holarctic region—from the Palaeotropics ( McInnes 1994 ). The conspecificity of European and African populations has yet to be demonstrated. Differential diagnosis: The new genus is compared with all two-macroplacoid hypsibiid genera having a rigid buccal tube, and with Acutuncus Pilato and Binda, 1997 (in Pilato and Binda 1997b ) due to the similar mode of egg deposition in the Acutuncus mariae group ( Vecchi et al . 2023 ). Table 3 shows the differences between all relevant taxa.