Avelona Qiu and Bouché, 1998

Avelona Qiu and Bouché, 1998

Type species. Octolasium ligrum Bouché, 1969 by original desigbation.

Included species: Avelona zicsii ( Bouché, 1972) comb. nov. Avelona yvesi sp. nov.

Etymology. This genus is named after Marcel Avel, a zoologist who researched earthworms in the first half of the XXth century.

Diagnosis. Small-sized (3–9 cm and 0.15–1.15 g) Lumbricini with less than 150 segments and absence of pigmentation. Prostomium epilobous. Setae closely paired. First dorsal pore in 3/4, 4/5 or 8/9. Male pores in 1/2 15 with well-developed porophores. Spermathecal pores in 9/10, 10/11, simple or double. Nephridial pores aligned or irregular. Clitellum starts in 26–29 and ends in 34–36. Tubercula pubertatis between 30–32 and 33–35(36). Lateral hearts in 6–11. Calciferous glands in 10–14 with diverticula or dilation in 10. Crop in 15–16. Gizzard in 17–18. Strongly developed glandular papillae in different segments. Typhlosole bifid to pinnate. Spermathecae simple or double in 10, 11, globular and intracoelomic. Two pairs of seminal vesicles in 11 and 12. Nephridial vesicles digitoid or J-shaped.

Differential diagnosis. Avelona shares with Gatesona a similar position of the clitellum, tubercula pubertatis and dorsal pores, and numerous genital papillae or chaetophores; however, they can be easily distinguished by their smaller size (30–90 mm vs 66–190 mm) and weight (0.15–1.15 g vs 1–3.5 g), the different type of nephridial vesicles (digitoid/J-shaped vs sigmoid or absent) and the number of seminal vesicles (two vs three or four).

Distribution. Avelona genus is only present in mainland France, between the 45 th –48 th parallel north( Fig. 2 View FIGURE 2 ).