A New Genus and Five New Species of Kalyptorhynchia (Platyhelminthes: Rhabdocoela) Discovered in Northern Japan Author Takeda, Naoya Marine Biological Research Institute of Japan, Yutaka-cho 4 - 3 - 16, Shinagawa, Tokyo 142 - 0042, Japan E-mail: bobamo 0 @ gmail. com & Corresponding author bobamo0@gmail.com Author Kajihara, Hiroshi Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060 - 0810, Japan text Species Diversity 2018 2018-05-25 23 1 1 11 http://dx.doi.org/10.12782/specdiv.23.1 journal article 4217 10.12782/specdiv.23.1 f1ac74c9-df4b-4402-a43b-e06abb6e8164 2189-7301 4583800 A9B333A2-FD81-476A-A805-D280C2194964 Proschizorhynchella caudociliata sp. nov. ( Figs 6 , 7 ; Table 1 ) Material examined. Holotype : ICHUM 4863 , adult, whole mount, 42°33′25″N , 141°55′42″E , Mukawa , Hokkaido , Japan , intertidal sand, 20 May 2012 . Paratypes : ICHUM 4262, 4264, 4265, three adults, whole mounts, same data as holotype . Description. Living animal body approximately 3.0 mm long and 0.3 mm wide ( Fig. 6 ). Proboscis 230–270 µm long, 70–80 µm wide ( Fig. 6 ). Pair of black eyes situated behind proboscis ( Fig. 6 ). Two testes, each 150–280 µm in diameter ( Fig. 6 ). Yolk gland 750 µm long, 110 µm wide ( Fig. 6A ). Two adhesive girdles present; anterior one located at level of posterior end of pharynx, posterior one near caudal end; each girdle composed of six adhesive papillae arranged in regular intervals ( Fig. 6A ). Pharynx 220 µm long, 150 µm wide ( Fig. 6 ). Pair of seminal vesicles, each 150–310 µm long, 10–30 µm wide, located posterior to pharynx ( Fig. 6A ). Male copulatory organ 160 µm long, 50 µm wide ( Fig. 6A ). Stylet cone shaped, 45 µm long, 12 µm wide, comprised of thin sclerotic sheet rolled up four times ( Figs 6A , 7 ). Ovary 120 µm long, 60 µm wide, located posterior to pharynx ( Fig. 6A, B ). Uterus, 90 µm long, 40 µm wide, located around ovary ( Fig. 6A ). Common genital pore opening on ventral side of body between two adhesive girdles ( Fig. 6A ). Bursa 190 µm long, 80 µm wide, located around common genital pore ( Fig. 6A ). Large oval structure (adhesive gland?) 120 µm long, 100 µm wide, located at the caudal end ( Fig. 6A ). Caudal end covered with long tactile cilia ( Fig. 6A ). Fig. 4. Freddius tricaudatus gen. et sp. nov. Images obtained from confocal laser scanning microscopy, ICHUM 4833 (paratype). A. Entire animal; B. Male copulatory organ. Abbreviations: c, male copulatory organ; gp, genital pore; m, mouth; ph, pharynx. Fig. 5. Freddius tricaudatus gen. et sp. nov. , cirrus spine, ICHUM 4832 (holotype). A. Illustration; B. Photomicrograph. Abbreviation: ci, cirrus spine. Etymology. The specific name refers to the long tactile cilia on the caudal region, which look like a brush. Remarks. Proschizorhynchella caudociliata can be distinguished from all congeners, except Proschizorhynchella papillata ( Doe, 1974 ) and P. shibazakii sp. nov. , based on the characteristics listed in Table 1 . These three species, however, can be distinguished on the basis of two characteristics: ( i ) four coils of the copulatory stylet in P. caudociliata and three in P. papillata and P. shibazakii and ( ii ) a vacuolated region and long tactile hair present near the caudal end in P. caudociliata but absent in P. papillata and P. shibazakii .