Helodrilus, HOFFMEISTER, 1845 EMENDED

Szederjesi, Tímea, Marchán, Daniel F., Csuzdi, Csaba, Sarbu, Serban M., Pavlíček, Tomáš, Krízsik, Virág, Martin, Patrick & Domínguez, Jorge, 2023, Three in one: molecular phylogeny of the genus Helodrilus (Crassiclitellata: Lumbricidae) with a description of two new genera and two new species, Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 197 (4), pp. 899-908 : 902-904

GENUS HELODRILUS HOFFMEISTER, 1845 EMENDED

Type species: Helodrilus oculatus Hoffmeister, 1845 .

Species included: Helodrilus cernosƲitoƲianus (Zicsi, 1967) .

Species putatiƲely included: Helodrilus samniticus Cognetti, 1914 ; Helodrilus phillipei Qiu & Bouché, 1998 ; Helodrilus turquini Qiu & Bouché, 1998 .

Diagnosis: Small worms (20–80 mm long, 1–2 mm wide) without pigmentation, setae lumbricine, closely paired. The clitellum begins around segment 20 and ends before 33. The tubercles cover 2–3 segments near the end of the clitellum. Spermathecae two or three pairs in 9/10, 10/11 or 9/10–11/12. Vesicles of two pairs in 11, 12. Calciferous glands adverticulate, weakly developed. Excretory system exoic, avesiculate.

Remarks: We have putatively included the species Helodrilus samniticus described from Italy, Helodrilus phillipei and Helodrilus turquini described from France in the emended Helodrilus based on their morphological similarity to the type species and also their west European distribution. Further molecular studies are needed to confirm these placements and, as well, the identity of the latter two species considered synonyms of Helodrilus oculatus by Szederjesi et al. (2014).

It is difficult to distinguish Helodrilus from the genera Gatesona Qiu & Bouché, 1998 sensu Marchán et al., 2021, and the new CoƲentina and Imetescolex by considering only morphological characters. However, Helodrilus differs from all of these genera in its smaller size and weakly developed or vestigial calciferous glands.

COVENTINA MARCHÁN, SZEDERJESI & CSUZDI