The tardigrade fauna of Australian marine caves: With descriptions of nine new species of Arthrotardigrada Jørgensen, Aslak Boesgaard, Tom M. Møbjerg, Nadja Kristensen, Reinhardt M. Zootaxa 2014 3802 4 401 443 7W4H Kristensen & Renaud-Mornant, 1983 Kristensen & Renaud-Mornant 1983 [238,859,1302,1328] Heterotardigrada Halechiniscidae Tholoarctus Animalia Arthrotardigrada 29 430 Tardigrada genus   Diagnosis (emended): Styraconyxinaewith a barrel-shaped outer epicuticle surrounding the trunk, the body itself is thin and elongated. Complete set of cephalic appendages. Cone-shaped primary clavae and secondary clavae enlarged surrounding both the internal and external cirri. Cirri A and E partially surround by funnel-shaped epicuticle folds. Leg sense organs always present on the first (se1) and fourth (se4) legs, though much smaller sense organs may be present on the second (se2) and third (se3) legs. Flagellum on the sense organ of the first leg always very long. Sense organ of the fourth leg partially enclosed in funnel-shaped epicuticular folds. Females have claws with a main hook, a basal accessory hook and a terminal accessory spur. Males and larvae might have simple claws in the external digits. Long buccal tube with two lateral projections at ca. the mid-point. Long and thin stylet supports articulate with the furcae. Placoids consist of a non-calcified cuticular lining, but three small calcified apodemes occur in the anterior part of the pharyngeal bulb. Mouth cone is terminal and protruding. Globular coelomocytes seem to be attached to the midgut. Sexual dimorphism in body size and claws.    Typespecies:  Tholoarctus natans Kristensen & Renaud-Mornant, 1983.  Additional species:The genus is currently monotypic. However a sub-species from Italy,  Tholoarctus natans pedunculatusD’Addabbo Gallo, de Zio Grimaldi, Morone De Lucia & Troccoli, 1992, has been described (D’Addabbo Gallo et al.1992).