Although it has been widely assumed that the presence of a visible clitellum closely parallels maturation of the female reproductive system in members of the family Erpobdellidae, this has never been thoroughly tested.Nephelopsis obscurawas maintained at 15°C and 20°C and fed 3x, 2x or 1x a week withad libitumprey. The leeches were examined weekly for the presence of a visible clitellum, spermatophores, the presence of vasa deferentia, and the stages of gametogenesis present determined. Feeding regime affected the time to the first occurrence of a visible clitellum with the leeches fed 3x a week exhibiting a clitellum 18–20 weeks before the first appearance of a clitellum in the groups fed 2x or lx a week at 15°C or 20°C. Regardless of feeding regime, all the leeches exhibited a second appearance of a clitellum after 41–48 weeks. The first appearance of a visible clitellum did not coincide with either spermatogenic or oogenic maturity, but at the second appearance of a clitellum leeches fed 3x and 2x a week showed fully mature ova at both temperatures. None of the leeches fed 1x a week ever showed spermatogenic or oogenic maturity. The presence of spermatophores was also not a reliable indicator of maturity with only 4% of the mature size range animals having an attached spermatophore. It is very probable that the presence of a visible clitellum is not a good indicator of maturity in most or all species in the family Erpobdellidae.