Marionina communis Nielsen & Christensen, 1959

(Figure 19)

Material examined. 7 specimens (three were deposited in the National Institute of Biological Resources, Korea; NIBRIV0000837804, NIBRIV0000866131, NIBRIV0000866132, in 70 % ethanol) .

Our observations agree with the description of Nielsen & Christensen (1959). Small worms (3–5 mm long, 230–250 μm wide at XII in vivo), segments 24–27. Chaetae straight, 2–3 per bundle. Clitellum saddle-shaped, gland cells in rows (Fig. 19C), glands absent midventrally. Brain incised posteriorly (Fig. 19A). Pharyngeal glands all separate dorsally, with ventral lobes, in VI largest (Fig. 19D). Coelomocytes oval 18–24 μm long, pale, finely granulated (Fig. 19B). 4 pairs of nephridia preclitellarly at 6/7–9/10. Dorsal blood vessel from XIII, blood colourless. Sperm funnels small, pear-shaped, 37–50 μm long, 1.5 times longer than wide (Fig. 19E). Penial bulbs small, compact (Fig. 19F). Spermathecae (Figs 19 G–H) with elongated ampulla, merging proximally and attached to oesophagus. Ectal ducts narrow and bearing at the ectal pore some glands of different size. One mature egg at a time (Fig. 19F).

Distribution and habitat in Korea. Mt. Gyebangsan, Nodong-ri, Yongpyeong-myeon, Pyeongchang-gun, Gangwon-do, Q. mongolica forest, N 37°42’27.92”, E 128°29’02.34”, 848 m asl.