Prostoma maculatum, Timofeev, 1911

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

7. Prostoma maculatum

(Annex Fig. 1G)

Description. Body length up to 14 mm, width up to 0.5 mm. Head not separated from remaining body. Body thickest at posterior 1/3, ending blunt-conically. With distinct brown cephalic patch behind first pair of eyes, as in Prostoma coronatum . Clusters of shiny, white glands present behind and in front of cephalic patch. Body colour from dirty yellow to reddish, less often pinkish and brown; anterior end of body transparent. Dorsally, more-orless sharp, rather large, white spots with red greenish and bluish tints being obvious. With transmitted light, these spots are transparent, delicate, pinkish-red colour, sometimes little noticeable. Location of spots on dorsal surface variable: sometimes arranged medially in single, sparse row; or 2–3, randomly located rows along midline; or sometimes scattered along the back without order (as in the attached figure). Rarely, smaller white specks of glands are mixed with the spots.

Localities. Dirty silt, off Darse (Annex Fig. 2 , VI). Sublittoral, silt, depth 16–18 m (Annex Fig. 2 , II). Among roots of Posidonia (Annex Fig. 2 , VII, VIII, IX). Small gravel with shells, depth 40 m (Annex Fig. 2 , XIX). Stones with bryozoans, 50 m ((Annex Fig. 2 , XXIII).

Remarks. The original figure (рис. 7) shows two accessory stylet pouches, each containing two or three accessory stylets; now Tetrastemma maculatum ( 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.