Apostylonychia Omar & Jung, 2024, gen. nov.

Apostylonychia gen. nov. ZooBank registration: urn:lsid:zoobank.org:act: CCDF5D43- C7A3-4D8B-AC14-302E7CCB0233. Diagnosis: Stylonychine with medium to large body size, in vivo 70–210 μm × 30–90 μm. Body obovate, with posterior half of cell distinctly narrower than anterior. Eighteen frontal–ventral–transverse cirri. Transverse cirri arranged in two groups of three left and two right. One right and one left row of marginal cirri. Frontal area in Stylonychia pattern, i.e. frontal cirri distinctly shifted to the right of the midline of the body. Undulating membranes in Stylonychia pattern. Six dorsal kineties, including two dorsomarginal rows; kinety 3 with simple fragmentation. Three narrowly spaced caudal cirri, slightly shifted to right, one each at posterior end of kineties 1, 2, and 4. Oral primordium originates left to leftmost transverse cirrus. Cirrus IV/3 produces anlagen IV–VI of the proter, cirri III/2, IV/2, and V/4 are involved in primordia formation. 18S rRNA gene: 591 (T); 632 (T); 669 (G); 698 (C); 709 (G); 1384 (T); 1404 (A); 1408 (A); 1726 (A). Etymology: The name is a composite of the Greek prefix apo - (derived from) and the genus group-name Stylonychia Ehrenberg, 1830, indicating that the new genus has a similar cirral pattern to that of Stylonychia, especially the arrangement of transverse cirri. Feminine gender. Type species: Apostylonychia baugilensis sp. nov. Species assignable: Apostylonychia baugilensis sp. nov. and Apostylonychia notophorides (Foissner, 2016) comb. nov. (original combination: Stylonychia notophorides Foissner, 2016).