Claparedrilus, Klinth, Marten J., Rota, Emilia & Erseus, Christer, 2017

Klinth, Marten J., Rota, Emilia & Erseus, Christer, 2017, Taxonomy of North European Lumbricillus (Clitellata, Enchytraeidae), ZooKeys 703, pp. 15-96 : 50-51

Claparedrilus gen. n.

Genus description/diagnosis.

Prostomium hemispherical. Head pore at 0/1. Epidermis with transverse rows of gland cells. Chaetae straight to sigmoid, without nodulus, grouped into two dorsolateral and two ventrolateral bundles per segment. Oesophageal appendages absent. Pharyngeal glands in four pairs, in IV–VII, converging but not connected dorsally, some with ventral lobes, but without secondary glands. Only nucleated coelomocytes present. Dorsal vessel originating intra or in segments posterior to clitellum. Nephridia with anteseptale made up of funnel on a short stalk. Clitellum more or less covering segments XII–XIII. Testes paired, surrounded by testis sacs; the latter forming compact mass with shallow lobes irregularly arranged. Penial bulbs round and compact. Midventral subneural glands present in XIV–XV. Spermathecae in V, attached to and usually communicating with oesophagus lumen, and with crown of glands surrounding ectal part of ectal duct. Spermathecae club-shaped with ampulla distinctly set off from duct. Spermathecal diverticula absent. Marine, living in the littoral zone.

Type species.

Claparedrilus semifuscoides sp. n.

Other species.

Claparedrilus semifuscus ( Claparède, 1961) comb. nov.

Etymology.

Clapare - from Claparède, the original author of the species C. semifuscus , a poorly defined species with which the type species for this new genus ( C. semifuscoides ) has been misidentified, and -drilus (latinized Greek) for worm.

Remarks.

The need for this new genus arose from the difficulty of placing the type species C. semifuscoides (which we previously referred to as L. semifuscus ) in the phylogeny of the Enchytraeidae . Molecular data had previously supported that this species was not a member of Lumbricillus and instead closer to, but not a member of, Globulidrilus and Bryodrilus ( Klinth et al. 2017; Martinsson et al. 2017). Both these genera share some traits with Claparedrilus , such as the shape of the spermathecae and nephridial anteseptale with small part of the nephridial body, but both have only three pairs of pharyngeal glands and are aquatic or terrestrial. The phylogenetic studies lacked representatives from several potential candidate genera of marine enchytraeids. Therefore, we compared the morphology of our species with these candidates (presented in Table 3), after which we still found support for the recognition of the new genus Claparedrilus . In particular, the combination of four pairs of pharyngeal glands, nephridia with a stalked funnel in the anteseptale and the presence subneural glands distinguishes this new genus.