Mixibius felix Lisi 2017, sp. nov.

• Main Author: Lisi, Oscar
• Format: Other/Unknown Material
• Language: unknown
• Published: Zenodo 2017
• Subjects: Biodiversity; Taxonomy; Animalia; Tardigrada; Eutardigrada; Parachela; Hypsibiidae; Mixibius; Mixibius felix; Acutuncus antarcticus; Antarc*; Antarctica; antarcticus; Victoria Land
• Online Access: https://doi.org/10.5281/zenodo.5620446; http://treatment.plazi.org/id/7E4D8B77FFEF312D609FFC57FF29FEAB

Mixibius felix sp. nov. Fig. 1, Table 1 Type locality. Vegetation Island, Victoria Land, Antarctica: 74°47′0″S, 163°37′0″E. Material examined. (collected by Prof. Salvatore Motta between 1990.12.15 and 1991.1.12): Vegetation Island (2 specimens, holotype and one paratype, slides No. 4535, from debris of the bottom of a small lake, together with Acutuncus antarcticus (Richters, 1904) and Diphascon dastychi Pilato & Binda, 1999; and Mariella Creek (8 specimens, slides Nos. 4540–4541, from debris of the bottom, together with Acutuncus antarcticus and Diphascon dastychi ). Type repository. Holotype and paratypes are preserved in the collection of Binda and Pilato in the Museum of the Department of Biological, Geological and Environmental Sciences (Section of Animal Biology “ Marcello La Greca ” of the University of Catania, Italy). Specific diagnosis. Colourless, cuticle smooth, eye spots present; bucco-pharyngeal apparatus of the Mixibius type (buccal tube rigid, without ventral lamina and with hook-shaped apophyses for the insertion of the stylet muscles); stylet supports inserted on the buccal tube at 65.7–68.0 percent of its length; pharyngeal bulb with apophyses and two rod-shaped macroplacoids; microplacoid and septulum absent; external claws of Isohypsibius type, internal claw of modified Isohypsibius type. Description of the holotype. Body 240 µm long, colourless, cuticle smooth, eye spots present in living specimens; bucco-pharyngeal apparatus (Figs. 1 A,B) of Mixibius type; the rigid and narrow buccal tube is 28.4 µm long and 2.5 µm wide ( pt = 8.8); the ventral lamina is absent; both the dorsal and ventral apophyses for the insertion of the stylet muscles hook-shaped, slightly asymmetrical with respect to the frontal plane (Fig. 1 B of a paratype, arrows a—ventral and b—dorsal): the dorsal apophysis is slightly more stumpy, with a blunt and swollen caudal apex. A short median cuticular thickening is present caudal to both these apophyses (the ventral less visible) (Fig. 1 B). The buccal armature is ...