Webbnesia, Núñez & Barnich & Monterroso, 2022

Núñez, Jorge, Barnich, Ruth & Monterroso, Óscar, 2022, A new genus and species of Polynoidae (Annelida: Polychaeta) from the Canary Islands, and update on taxa present in the Northeast Atlantic, European Journal of Taxonomy 846 (1), pp. 55-74 : 61-63

Genus Webbnesia gen. nov.

urn:lsid:zoobank.org:act:33FB3584-DCFC-4B0E-9D1D-ED8AF67F15E9

Tables 2–3

Type species

Webbnesia maculata gen. et sp. nov. designated herein.

Diagnosis

BODY. Flattened dorsoventrally, short, with fewer than 40 segments, more or less covered by elytra dorsally.

ELYTRA. 15 pairs on segments 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 26, 29 and 32. PROSTOMIUM. Bilobed, without cephalic peaks, with three antennae. Median antenna inserted in anterior notch, lateral antennae inserted ventrally. Two pairs of eyes.

PARAPODIA. Biramous, notopodium reduced and neuropodium elongate. Notopodium with aciculum penetrating distally. Neuropodium with elongate prechaetal lobe and shorter postchaetal lobe; prechaetal acicular lobe with minute (i.e., reduced) supra-acicular process, aciculum penetrating subdistally.

CHAETAE. Notochaetae and neurochaetae stout, with rows of spines and entire tip.

Etymology

The genus name is a combination of the name Webb and the Greek word ‘ nes ’ (= ‘island’); gender feminine. ‘Webbnesia’ refers to a new ecoregion defined by Freitas et al. (2019) and co-authored by one of us (JN) which includes the Canary, Savage and Madeira Islands.

Remarks

Among the genera currently attributed to Polynoinae sensu lato, only Hermadion Kinberg, 1856 , Antinoe Kinberg, 1856 and Malmgrenia McIntosh, 1874 (see Pettibone 1993; Bock et al. 2010 and Barnich et al. 2017) share the following diagnostic characters with Webbnesia gen. nov.: 15 pairs of elytra, fewer than 50 segments (i.e., short-bodied), cephalic peaks absent, noto-and neurochaetae all of same type, stout, without semi-lunar pockets.

Webbnesia and Hermadion have ventrally inserted lateral antennae, but the shape of their parapodia is different. The notopodium of Hermadion is prominent, nearly as long as the neuropodium, while the new genus is characterised by a minute, reduced notopodium (see Tables 2–3 ).

In Malmgrenia and Antinoe the parapodia are similar to those of Webbnesia , but the main difference is the insertion of the lateral antennae, which is ventral in Webbnesia and terminoventral in the two other genera.

Among the polynoid genera sharing the diagnostic characters listed above, the combination of ventrally inserted antennae and a reduced notopodium is unique and justifies the erection of a new genus (see Table 2 ).