Catriona osezakiensis Martynov, Korshunova, Lundin, Malmberg, 2022

カトリオーナ・オセザキエンシス Catriona osezakiensis
Photographed by
nobuhiko KIMOTO Nobuhiko
Futou beach, Tago, Futou, Dougashima, Higashiizu, Japan
Water temperature
Etymology. Afte r the famous in Japan location for diving – Osezaki.D e s cription. External morpholo gy. The length of the holotype is 12 mm (Figure 8 A1–A2). The body is moderately narrow. The rhinophores are similar in size to the oral tentacles, smooth. The cerata are relatively long, from elongated, fusiformes to lampshaped. Up to 5 pre-anal ceratal rows. Anal opening acleioproctic. The foot is narrow, anteriorly rounded, no foot corners. Colour. The ground colour is transluce nt whitis h. Rhinopho res cover with yellow is h to orange pigment in the basal half, oral tentacles devoid of orange pigment. Both rhinophores and oral tentacles cover towards the top with opaque white to yellowish pigment. The digestive branches in the cerata are pale brownish with a pink hue. Towards the top of the cerata there are broader opaque whitish band and narrower yellowish band, which can be sometimes orange. The tip of cerata translucent with opaque whitish pigment. White pigment also covers some dorsal areas. There are no distinct white lines througho ut most of the length of the cerata.Digestive system. The jaws are moderately broad. The masticatory processes of the jaws bear a single row of up to 50 and more fine complex tubercles, which represent undeveloped or partly damaged bristles and also distinct bristles comprised from a set of tightly packed filaments (Figure 8 A5, A6). The radular formula is at least up to over 125 x 0.1.0. The central tooth is broad, with significantly retracted cusp with ca. 4–6 larger lateral denticles, and further ca. 1–9