Paradalhousia, Salazar-Vallejo, 2020

Salazar-Vallejo, Sergio I., 2020, Revision of Leocrates Kinberg, 1866 and Leocratides Ehlers, 1908 (Annelida, Errantia, Hesionidae), Zootaxa 4739 (1), pp. 1-114 : 81

Paradalhousia n. gen.

urn:lsid:zoobank.org:act:893F4CF5-8D89-46CB-A616-D02FD78B98AE

Type species. Leocrates anomalus Chamberlin, 1919 .

Diagnosis. Hesioninae with two lateral antennae, and one median antenna on dorsal prostomial surface. Palps biarticulate, palpophores large, massive, palpostyles smaller, blunt. Eyes dark, black, brown or reddish, anterior ones larger than posterior ones, sometimes approaching each other in lateral view. Nuchal organs lobes U-shaped. Pharynx with single upper and lower jaws, and a marginal ring of denticles. Parapodia sesquiramous along chaetigers 1–3, biramous thereafter. Notochaetae from chaetiger 4, subdistally denticulate, often abundant, usually very long, reaching neurochaetal tips. Neurochaetae compound falcigers, blades bidentate, guards approaching subdistal tooth.

Etymology. The genus-group name is derived from Dalhousia McIntosh, 1885 , with the Greek prefix Para - (= near) to emphasize their close resemblance.

Gender. Feminine, as the stem genus-group name.

Remarks. Paradalhousia n. gen. and Dalhousia McIntosh, 1901 are very similar by having biarticulate palps, pharynx with jaws, U-shaped nuchal organs lobes, and sesquiramous parapodia anteriorly and biramous posteriorly. Their main differences rely in the pharynx armature and in the pigmentation of neurochaetae. In Paradalhousia there are single, fang-shaped upper and lower jaws, and a marginal circle of denticles, and neurochaetae are pale, whereas in Dalhousia the upper jaw is double, T-shaped, and the ventral jaw is a transverse plate, there are no marginal denticles, and neurochaetae are often brownish.