Cheliplana schilkei Noldt, 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 : 480

Cheliplana schilkei Noldt, 1989

Material examined. None.

Known distribution. Sylt, Germany ( Noldt 1989).

Remarks (summarised from literature). According to Noldt (1989), live specimens are transparent and measure ~ 1.7 mm. The proboscis has relatively long hook supports (23–25 μm), armed with short, 12-µm-long hooks. The postrostral bulb is up to 50 μm long. Proboscis sidepieces are lacking. The prepharyngeal pouch lacks spines and opens on the ventral side below the brain.

A single testis is present. The seminal vesicle is unpaired and enters the proximal side of the copulatory bulb, along with numerous prostatic glands. The bulb is surrounded by longitudinal muscles and reaches a length of 190–220 μm and a diameter of 35–45 μm. An internal seminal vesicle surrounded by prostatic glands is present in the proximal part of the copulatory bulb. The internal seminal vesicle and gland ducts merge to form a 110– 125-µm-long ejaculatory duct. Distally, the ejaculatory duct is differentiated into a 70–80-µm-long, armed cirrus. The proximal part of the cirrus is armed with 6–7.5-µm-long spines. Distally, the cirrus has no spines, but bears sclerotised ridges. It is everted to form a 15–25-µm-long penis papilla with a diameter of 25–30 μm. Parenchymatic tissue surrounds the ejaculatory duct and the cirrus.

A uterus is surrounded by glands and opens into the common atrium. A vagina interna also connects to the atrium. The proximal part of the vagina interna connects to a vacuolated bursa, which in turn connects to the adjacent ovary via a sclerotised spermatic duct. The ovary lies alongside the copulatory apparatus and connects to the common genital atrium through a short female duct. Basophilic glands empty into the atrium close to the common genital opening. The dorsal part of the genital atrium receives acidophilic glands. A single vitellarium extends from the pharynx bulb to the bursa.