This is an introduced European species of earthworm. Reynolds (1977) provides the following description: “Length 30-70 mm, diameter 3-5 mm, segment number 80-138, prostomium epilobic, first dorsal pore 4/5. Clitellum xxviii, xxix-xxxvii. Tubercula pubertatis small sucker-like discs on xxxi, xxxiii and xxxv. Setae closely paired, AA>BC, DD = 1/2 C anteriorly, and DD <1/2 C posteriorly. Setae c and d on x often on white genital tumescences. Males pores in xv with large elevated glandular papillae extending over xiv and xvi. Seminal vesicles, four pairs in 9-12. Spermathacae, three pairs opening on level cd in 8/9, 9/10 and 10/11. Colour variable, frequently green but sometimes yellow, pink or grey. Body cylindrical.”
Source: Reynolds, John W. 1977. The Earthworms (Lumbricidae and Sparganophilidae) of Ontario. Life Science Miscellaneous Publications, Royal Ontario Musuem, Toronto, with permission.