Stylochus Ehrenberg, 1831

Bulnes, V. N., Faubel, A. & Park, J. - K., 2005, Two new marine species from South Korea with remarks on the family Stylochidae (Acotylea, Polycladida, Plathelminthes), Journal of Natural History (J. Nat. Hist.) 39 (23), pp. 2089-2107 : 2094

Genus Stylochus Ehrenberg, 1831

Diagnosis (emend. nov.)

Stylochidae with large, highly ruffled pharynx. Tentacular, cerebral, marginal, and often frontal eyespots present. Male copulatory apparatus with seminal vesicle not anchorshaped, prostatic vesicle, and unarmed penis papilla. Lang’s vesicle absent. Prostatic vesicle with polyglandular lining. Body often with intensively undulated margins.

Type of the genus: Stylochus suesensis Ehrenberg, 1831 .

Stylochus neapolitanus ( Delle Chiaje, 1841) Lang, 1884

( Figure 3E )

Planaria neapolitana Delle Chiaje 1841 , Volume III, p 133; Volume V, p 112, Plate 109 Figures 13–15, 22.

Material examined

Voucher specimen. No. 67550, one specimen sagittally sectioned, locality: Naples , Gulf of Naples, Tyrrhenian Sea, deposited in SMNH .

Morphological notes

In the following, only morphological characters which deviate from the description of Meixner (1907, p 422–425) are added or re-described.

Reproductive system. Male genital system with ventral testes follicles, separate entrance of vasa deferentia into the voluminous, elongate seminal vesicle, prostatic vesicle and penis papilla housed in a small male atrium. Male and female gonopores separate. Prostatic vesicle ( Figure 3E ) oval, with finger-like extensions; inner glandular lining is connected to many extra-vesicular glands lying rather distant from the muscular wall of the prostatic vesicle (polyglandular type).

Figures

Figure 3. Diagrammatic reconstruction of prostatic vesicles of Stylochidae. Monoglandular types: (A–C) Cryptostylochus koreensis sp. nov.: (A) medio-sagittal section through the prostatic vesicle, (B) peripheral section through the prostatic vesicle, (C) diagrammatic reconstruction of the prostatic vesicle; (D) Cryptostylochus hullensis Faubel and Gollasch. Polyglandular types: (E) Stylochus neapolitanus (Delle Chiaje); (F) Distylochus pusillus Bock. Scale bars: 70 mm.