Piguet, 1913
Description
Middle-sized worms, with two sigmoid, simple-pointed chaetae per bundle. Chaetae about 100 µm long, with distal nodulus. External secondary annulation beginning from III or IV, with narrow anterior ring in each segment. Male pores in X, spermathecal pores also in X (before male pores), female pores in 10/11; all pores behind ventral chaetae of corresponding segment. Clitellum in X-XI. Internal characters: Pharyngeal glands in IV-VII. Chloragogen cells on digestive tube begin from VI or VII. Testes in IX, ovaries in X. Large male funnels on 9/10, vasa deferentia make a loop in X and fall into apical end of roundish or pear-shaped atria. Ectal end of atrium forms a large penis often protruding from male pore in preserved specimens. Spermathecae in X, with spherical to elongate ampulla and clearly limited, often twisted duct. Length 8-15 mm, segment number 53-65. Externally very similar to several lumbriculids, particularly to those of the genus Trichodrilus; differing from them in the location of testes and male pores in different segments. Differing from Dorydrilus tetrathecus in having one pair of spermathecae, and from Dorydrilus mirabilis in the location of spermathecal pores in X.
Burrowing in sediment.
Distribution
Europe.
Ecology
In freshwater, mainly in groundwater.
Reproduction
Sexual only. Eggs laid in cocoons.
Literature
Piguet, 1913: 141-145, Fig. 12, Piguet and Bretscher, 1913: 158-159, Figs 39B,C; Hrabe, 1936a: 3-7, Figs 1-2; Hrabe, 1960: 256-258, Figs 15-16; Cook, 1967: 366-367, Fig. 8. ; Cook, 1971b: 649, Fig. 10.1A,D; Kasprzak, 1981: 186, Figs.733-736.