Revision of Leocrates Kinberg, 1866 and Leocratides Ehlers, 1908 (Annelida, Errantia, Hesionidae)
Author
Salazar-Vallejo, Sergio I.
text
Zootaxa
2020
2020-02-18
4739
1
1
114
journal article
23993
10.11646/zootaxa.4739.1.1
d3e60fb6-636b-4e03-b55a-0e910f9a468e
1175-5326
3672547
544B9C82-BF33-4EA1-9411-E1A307137466
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.