Limnodrilus profundicola (Verrill, 1871)

Cui, Yongde, He, Xuebao, Peng, Yu & Wang, Hongzhu, 2015, Records of Naididae and Lumbriculidae (Clitellata) from Tibet, China, with description of a new species of Nais, Zootaxa 3956 (4), pp. 513-530 : 526-527

20. Limnodrilus profundicola (Verrill, 1871)

( Figure 7 )

Limnodrilus helveticus Piguet. Liang 1962: 23 –24.

Limnodrilus profundicola (Verrill) . He 2011: 107 –108.

Material. Lake Yamzhao Yumco, shoreline, ST53, 1 mature specimen, mounted in Canada balsam (dissected). In 10% formalin: Yarlung Zangbu River, ST1, 2 spms; ST2, 1 spm. Lake Namco, ST56, 2 spms.

Description. Length 19 mm, width 1.0 mm anteriorly, 0.5 mm posteriorly, 57 segments. Prostomium conical. Coelomocytes absent. No hairs. Ventral and dorsal chaetae all the same shape, distal teeth shorter or equal to proximal, nodulus distal. In anterior segments dorsally and ventrally 6–9 and 6–11 chaetae per bundle, respectively, 4–7 per bundle posteriorly. Vasa deferentia ( Fig. 7 B, vd) long, 23–30 Μm wide, 5–8 Μm wall thick, with cilia. Atrium ( Fig. 7 B, at) of fusiform shape, 55 Μm wide, 238 Μm long, about 4x as wide as long. Prostate gland ( Fig. 7 B, pr) large, solid, lobulated, attached to middle portion of atrium. Ejaculatory ducts ( Fig. 7 B, ed) present, 15–25 Μm wide. Penis sheath ( Fig. 7 B, ps) cylindrical, 65 Μm wide at proximal base, 290 Μm long, 5x as long as wide, thick-walled. Penis sheath widest at proximal base, gradually narrowing distally, narrowest in the middle, slightly wider at the distal top; distal end expanding abruptly to form a head of circular form, which is generally reflected back over the tube. Spermathecae ( Fig. 7 A, sa) paired in X, pear-shaped. Spermatozeugmata ( Fig. 7 A, sz) worm-like, 4 of them in ampulla. Duct ( Fig. 7 A, sd) short, expanded in the middle ( Fig. 7 A, sv), with fine sperm bundles in the cavity ( Fig. 7 A, sb).

Remarks. This species was recorded as Limnodrilus helveticus in Heilongjiang, Xinjiang, Qinghai Province in China ( Liang 1962; Wang & Cui 2007). Following Brinkhurst & Jamieson (1971), L. helveticus is a junior synonym of L. profundicola ; hence the record of L. helveticus recorded in Liang (1962) should be changed to Limnodrilus profundicola . Our material agrees with previous descriptions ( Brinkhurst & Jamieson 1971; Hrabě 1979; Timm 1999), notably in the shape of the penial sheaths, being 5x as long as wide and with mushroom-like distal end. First record from Tibet.

Figures

FIGURE 7. Limnodrilus profundicola (Verrill, 1871). A. Spermatheca. B. Male duct. Scale bar 80 Μm.