What is a ‘ strong’ synapomorphy? Redescriptions of Murray’s type species and descriptions of new taxa challenge the systematics of Hypsibiidae (Eutardigrada: Parachela) Author Gąsiorek, Piotr Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30 - 387 Kraków, Poland & Natural History Museum of Denmark, University of Copenhagen, Øster Voldgade 5 - 7, DK- 1350, Universitetsparken 15, DK- 2100, Copenhagen, Denmark piotr.lukas.gasiorek@gmail.com Author Blagden, Brian Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30 - 387 Kraków, Poland Author Morek, Witold Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30 - 387 Kraków, Poland & Tree of Life Programme, Wellcome Sanger Institute, Hinxton, Cambridge CB 10 1 SA, United Kingdom Author Michalczyk, Łukasz Department of Invertebrate Evolution, Institute of Zoology and Biomedical Research, Faculty of Biology, Jagiellonian University, Gronostajowa 9, 30 - 387 Kraków, Poland text Zoological Journal of the Linnean Society 2024 2023-11-14 202 1 1 63 http://dx.doi.org/10.1093/zoolinnean/zlad151 journal article 10.1093/zoolinnean/zlad151 0024-4082 14243740 044A402-2A0F-4135-9410-7DE081CB11C4Corresponding Platicrista carpathica Gąsiorek sp. nov. ZooBank registration: urn:lsid:zoobank.org:act: 4D82EEA5- 92A6-4061-A43E-F4C09B97F307 Material examined: 24 individuals in total (for details, see Supporting Information, Table S1 ). Type material: Holotype (slide PL.188.01 ) and 18 paratypes (slides PL.088.01 , PL.188.02 , PL.201.01 , PL.245.01–3 , PL.249.01 , PL.287.03 , PL.296.01 , and PL.373.01 ) from Poland , various locales in the Tatra Mountains (Supporting Information, Table S1 ), are deposited in the Institute of Zoology and Biomedical Research, Jagiellonian University, Kraków. Figure 19. Caudal sculpturing of Platicrista angustata (PCM) : A, juvenile; B, C, adults. Scale bars: 10 μm. Description: Body massive ( Table 8 ), white and elongate, with a blunt cephalic part ( Fig. 24 ). Cuticle without pores, but with irregular wrinkling caudally and rudimentary granulation in the lateralmost portions of the dorsocaudal body part ( Fig. 25 ). Cribriform areas not visible under PCM. Legs short and plump. Eyes absent in unmounted animals. Buccopharyngeal apparatus of the Platicrista type ( Fig. 26A ): OCA not visible under PCM; annulation of the pharyngeal tube simple and comprising tightly merged annuli; stylet supports inserted at the junction between the buccal and pharyngeal tubes; furcae of the Platicrista type ; pharyngeal apophyses absent; pharynx oval, with two bar-like macroplacoids: the first much shorter than the second (1 <2). Figure 20. Claws of Platicrista angustata : A, claws III (neotype, PCM); B, claws IV (neotype, PCM); C, claws I (SEM); D, claws III (SEM); E, claws IV (SEM). Empty white arrowheads indicate pseudolunulae. Scale bars are in micrometres. Claws of the Hypsibius type , large and slender ( Fig. 26B–D ). Accessory points tightly adjacent to primary branches of the external/posterior claws, but with tips divergent from the primary branches of the internal/anterior claws. A weakly developed indentation on all claw bases. Septa between claw parts absent. Pseudolunulae smooth. Cuticular bars absent. Pulvini visible when legs are oriented suitably ( Fig. 26C ). Etymology: The name signifies terra typica . An adjective in nominative singular. Differential diagnosis: There are four congeneric species characterized by an absence of cuticular bars on their legs and the presence of a poorly developed or entirely absent dorsal granulation: P. aluna , P. angustata , P. nivea and P. horribilis (granulation absent). Platicrista carpathica can be differentiated from them based on: • P. aluna , the absence of striation of the buccal tube; • P. angustata , see above; • P. horribilis , the indentation of the pseudolunulae under claws IV (absent in P. carpathica vs. present in P. horribilis ) and the divergence of accessory points from the primary branches of the external and posterior claws (not divergent in P. carpathica vs. clearly divergent in P.horribilis ; compare Figs 26B–D and 27B–D ); • P. nivea , the presence and form of the caudal granulation (weakly developed only in the lateralmost part of caudal trunk in P. carpathica vs. strongly developed on the entire caudal trunk in P. nivea ).