Cheliplana californica Karling, 1989

Gobert, Stefan, Diez, Yander L., Monnens, Marlies, Reygel, Patrick, Van Steenkiste, Niels W. L., Leander, Brian S. & Artois, Tom, 2021, A revision of the genus Cheliplana de Beauchamp, 1927 (Rhabdocoela: Schizorhynchia), with the description of six new species, Zootaxa 4970 (3), pp. 453-494 : 466

Cheliplana californica Karling, 1989

Fig. 9E

Material examined. New material. CANADA • British Columbia, Vancouver, Wreck Beach ; 49°15’48”N, 123°15’46”W; 10 Apr. 2015; 1 whole mount; superficial sediment with coarse fraction near rocky headland in the lower intertidal; MI4181 .

Reference material. 2 whole mounts, including the holotype, and 1 serially sectioned specimen from California ( SMNH Type 6799; SMNH 90402 ) .

Known distribution. Elkhorn Slough, Monterey Bay, California, United States ( Karling 1989).

Remarks. Our observations correspond to the original description by Karling (1989). Specimens are ~ 1 mm long and colourless. The caudal haptic girdle is described as consisting of approximately 40 papillae. The cylindrical pharynx is connected to the mouth through a long prepharyngeal tube lined with hair-like bristles. A pair of testes lies alongside the pharynx and the two testes are connected to each other across the oral tube. The oviform male copulatory bulb measures ~95 μm in the Canadian specimen (cb, Fig. 9E ) and 118–123 μm in specimens from California (n = 2). The copulatory bulb encloses a short ejaculatory duct, which distally continues in an asymmetrically armed cirrus (ci, Fig. 9E ). The cirrus in the specimen from Canada is smaller (~30 μm) compared to the cirrus in Californian specimens (43–47 μm, n = 2). The cirrus spines measure 4–10 μm, increasing in length towards the distal end on one side, while decreasing in length towards the distal end on the other side. Distally, the cirrus ends in a short, sclerotised tube, which may be everted to form a cylindrical papilla.

The yolk glands are paired. A non-muscular vagina externa is present, with the opening lying directly anterior to the gonopore. The external vagina opens into a large bursa, which is connected to the single ovary through a spermatic duct.

Figures

FIGURE 9. A–D. Cheliplana setosa Evdonin, 1971 from British Columbia, Canada. A. Live specimen. B. Detail of the male copulatory organs in a live specimen. C. Detail of the proboscis with proboscis hooks and hook supports in a wholemounted specimen. D. Detail of the male copulatory bulb with prostate vesicle and tripartite cirrus in a whole-mounted specimen. E. Cheliplana californica Karling, 1989 from British Columbia, Canada. Detail of the male copulatory bulb with cirrus in the whole-mounted specimen. Scale bars: A = 100 μm; B = 20 μm; C = 10 μm; D–E = 20 μm.