Annenkova Salazar-Vallejo 2012, n. gen.

Annenkova n. gen.

Type species: Flabelligera mastigophora Annenkova, 1952.

Diagnosis. Body blunt anteriorly, tapering posteriorly. Tunic thick, fragile, soft, including mostly individual papillae, papillae not forming groups. Cephalic cage chaetae long, mostly exposed. Notochaetae long, multiarticulated capillaries with short articles basally, medium-sized medially, long distally; neurohooks usually one per ramus, multiarticulated in anterior chaetigers, oligoarticulate in median chaetigers, anchylosed in posterior chaetigers; crest thin, apparently articulated, tapering into a variably curved mucro. Free-living.

Etymology. The genus is named after the late Nadezhda Pavlovna Annenkova-Chlopina, in recognition of her many publications on Russian polychaetes, and especially for her publications on flabelligerids. Her telegraphic style was combined with a good eye for recognizing diagnostic features, a combination that is regretfully fading out in some current taxonomical studies.

Remarks. Annenkova n. gen. differs from Flabelligera Sars, and from Flabegraviera n. gen., by having a thin, loosely arranged tunic and especially because it has a special type of neurohook with a long, tapering, thin crest that looks articulated. The tunic might be eroded by dredging or during sample sieving. However, the tapering thin crest in the neurohooks is a unique feature and a true autapomorphy for the group. The apparently articulated structure is rather a difference in the transparency of the inner core, being completely hyaline distally and slightly more fibrous subdistally, but there is no articulation.

Distribution. Currently, the genus includes only the type species and is restricted to the Okhotsk, Chukchi and Bering seas.