Prostoma viperula, Timofeeva, 1912

Kajihara, Hiroshi, 2025, A taxonomic revision of the freshwater monostiliferous hoplonemertean genus Prostoma Dugès, 1828 (Nemertea: Eumonostilifera): a radical solution or an over-lumping?, Zootaxa 5646 (4), pp. 451-500 : 487

8. Prostoma viperula

[No illustration in the original description]

Description. Up to 20 mm long, about 0.5 mm wide. Extremely graceful nemertean with head weakly demarcated from body; body somewhat thicker than in middle portion, greenish, transparent; cephalic furrows coloured slightly reddish brown. Single, bright white mid-dorsal stripe (glandular) stretching from rear end of head to tail; irregularly shaped white processes laterally branching off from mid-dorsal stripe.

Locality. Passable, among roots of Posidonia (Annex Fig. 2 , IX). Quite abundant.

Remarks. Now Tetrastemma viperula ( Timofeev, 1911) .

Figures

FIGURE 2. Prostoma clepsinoides Dugès, 1828 from Lake Biwa, Japan. A, Entire specimen in living state, lost after photographed. B, C, Transverse sections through proboscis anterior chamber; white arrowheads pointing to proboscis nerves. D, Sagittal section through the opening of the oesophagus–rhynchodaeum complex; black arrowheads pointing to cilia on ventral wall of oesophagus; anterior to the left. E, Magnification of D, showing sparse cilia on ventral wall of oesophagus, indicated by black arrowheads. F, Magnification of D; black arrowhead pointing to longitudinal muscle fibre along rhynchodaeum.G, Sagittal section near rhynchodaeal opening; anterior to the right. B, D, E, F, ICHUM 6272; C, ICHUM 6277; G, ICHUM 6273.