Eupolymnia gili, Lavesque & Daffe & Londoño-Mesa & Hutchings, 2021

Lavesque, Nicolas, Daffe, Guillemine, Londoño-Mesa, Mario H. & Hutchings, Pat, 2021, Revision of the French Terebellidae sensu stricto (Annelida, Terebelliformia), with descriptions of nine new species, Zootaxa 5038 (1), pp. 1-63 : 19-20

Eupolymnia gili n. sp.

Figure 7

Material examined. Holotype. MNHN-IA-TYPE 2020, complete specimen, gravid, English Channel, Blainvillesur-Mer, 49°04’20”N 1°39’06”W, low intertidal, February 2020, few posterior parapodia used for molecular analysis. Paratypes. MNHN-IA-TYPE 2021, one posteriorly incomplete specimen, English Channel, Blainville-sur- Mer, 49°04’20”N 1°39’06”W, lower intertidal, February 2020, few parapodia used for molecular analysis, mounted for SEM. AM W.53325, one posteriorly incomplete specimen, English Channel, Blainville-sur-Mer, 49°04’20”N 1°39’06”W, low intertidal, February 2020, few posterior parapodia used for molecular analysis .

Additional material. SMA-BR-Eupoly-04, one specimen posteriorly incomplete, Northeastern Atlantic Ocean , Brittany, Bay of Brest , 48°21’28”N 4°26’38”W, depth 7 m, May 2018, posterior part used for molecular analysis. SMA-BR-Eupoly-05, one posteriorly incomplete specimen, Northeastern Atlantic Ocean , Brittany, Bay of Brest , 48°21’28”N 4°26’38”W, depth 7 m, May 2018, posterior part used for molecular analysis. SMA-COR-Tere-01, one posteriorly incomplete specimen, Mediterranean Sea, Corsica Cape, 42°47’12”N 9°19’48”E, depth 41 m, May 2019, posterior part used for molecular analysis .

Description. In life, red body covered by with white spots, including branchial stems and branches, buccal tentacles pinkish, prostomial eyespots black ( Fig. 7A ).

Large sized species, holotype complete 82.5 mm long and 6.8 mm wide (4.1–7.2 mm) for about 100 segments. Transverse prostomium attached to dorsal surface of upper lip; basal part with continuous row of red or black eyespots, without mid-dorsal gap, with eyespots well separated from each other ( Fig. 7A–B ); distal part forming a shelf-like tentacular membrane; buccal tentacles thick and grooved ( Fig. 7A ). Peristomium forming lips; hood-like upper lip, rectangular, wider than long with convoluted margin; lower lip swollen, wider than high ( Fig. 7C ).

Arborescent branchiae present on SG II–IV, first pair the longest, situated slightly more dorsally, third pair the shortest, situated more laterally; with short and thick branchial filaments, branching dichotomously from long basal stem ( Fig. 7A–C ).

Segment I well visible, ventrally developed, forming ventral lobe below lower lip ( Fig. 7B–C ). Three pairs of thick, translucent lobes on SG II–IV; SGII with one pair of short rounded ventro-lateral lobes, dorsal margins aligned with ventral edges of following neuropodia; SGIII and IV with short semi-circular lateral lobes, about the same size, situated progressively more dorsally, lobes of SG IV almost aligned with neuropodia of SG V ( Fig. 7A–C ).

Anterior segments with glandular, trapezoidal, slightly corrugated anteriorly to smooth mid-ventral shields, on SGII–XVII, last three shields distinctly shorter and hexagonal; mid-ventral groove extending posteriorly from SG XVII ( Fig. 7D ).

Rectangular notopodia beginning from SG IV, extending for 17 segments, until SG XX, laterally aligned, notopodia of first two pairs shorter and dorsally directed ( Fig. 7A–C ). Narrowly-winged notochaetae in two rows, first row shorter ( Fig. 7E ).

Neuropodia present from SG V, as low ridges until end of notopodia ( Fig. 7B–C ), as rectangular pinnules with pointed dorsal tip thereafter ( Fig. 7D ). Neurochaetae throughout as short-handled avicular uncini, arranged in completely intercalated double rows on SG XI–XX in a face-to-face arrangement. Uncini with well-developed digitiform heel and rounded prow, pointed dorsal button inserted closer to prow than to base of main fang, elongate convex base, and main fang surmounted by a crest with a first row of two large teeth, and a second row with one large middle tooth and several small teeth ( Fig. 7F–G ).

Nephridial papillae on SG III–V, inserted posteriorly to bases of branchiae and dorsally to notopodia; genital papillae on SG VI–IX, as openings between parapodial lobes, inserted posteriorly to notopodia ( Fig. 7B ).

Pygidium discoidal, surrounded by short papillae.

Tube made of coarse sand.

Etymology. This species is named after João Gil, an excellent polychaete taxonomist, in recognition of his work on European Fauna of Polychaeta. His thesis is undoubtedly the best reference to correctly identify French worms since Fauvel (1927). This species name was given in agreement with Anne-Laure Janson, Benoit Gouillieux, Vincent Le Garrec and Jean-Philippe Pezy who collected the studied material.

Habitat. Under rocks and in coastal maërl (rhodolith) beds, lower intertidal to shallow waters (depth 7–41 m).

Type locality. Blainville-sur-Mer , English Channel, France, 49°04’20”N 1°39’06”W .

Distribution. French coasts: English Channel (Blainville-sur-Mer), Bay of Biscay (Bay of Brest), Mediterranean Sea ( Corsica Cape).

Remarks. Among European species, Eupolymnia gili n. sp. differs from E. meissnerae n. sp. by the presence of long branchial stems which are inconspicuous in E. meissnerae n. sp., by eyespots arranged in a continuous band instead of the eyespots being separated by a mid-dorsal gap as in E. meissnerae n. sp. and by uncini surmounted by two and one large teeth on the first and second rows above the main fang, respectively, instead of uncini surmounted by two large teeth in the two first rows for E. meissnerae n. sp. Eupolymnia gili n. sp. also differs from E. meissnerae n. sp. by the absence of a ventral crest on SG II, by the presence of thick and translucent lateral lobes on SG II–IV and the presence of abdominal neuropodia with pointed dorsal projections. Finally, E. gili n. sp. differs from E. meissnerae n. sp. by the colour pattern of live specimens. Live material of E.gili n. sp. have a red body covered by white spots whereas there is an orange pattern in E. meissnerae n. sp.

Eupolymnia gili n. sp., E. lacazei n. sp. and E. nebulosa belong to the same complex of “strawberry worms” due to their colourful pattern, with red body covered by white spots. However, E. gili n. sp. differs from E. lacazei n. sp. by the absence of ventral crest on SG II, by the presence of thick and translucent lateral lobes on SG II–IV and the presence of abdominal neuropodia with pointed dorsal projections.

Finally, Eupolymnia gili n. sp. differs from E. nebulosa ( Montagu 1819) by the presence of long branchial stems which are absent for E. nebulosa , by the absence of bilobed lateral lobes on SG III, and by the presence of 17 ventral shields instead of 10 for E. nebulosa as observed by Hutchings & Glasby (1988) and Capa & Hutchings (2006) on several specimens sampled close to the type locality. The two species also differ by the shape of uncini. Their dorsal button are situated closer to the prow than to the base for E. gili , and at midway for E. nebulosa .

Figures

FIGURE 7. Eupolymnia gili n. sp. Additional material SMA-BR-Eupoly-04 (A), holotype MNHN-IA-TYPE 2020 (B–C, E), paratype AM W.53325 (D–F), SEM paratype MNHN-IA-TYPE 2021 (G). A. Anterior end, lateral view, live specimen; B. Anterior end, lateral view; C. Anterior end, ventral view; D. Posterior part, lateral view; E. Notochaetae, SG X; F. Uncinus, SG XIII; G. Uncini, SG VII. Abbreviations: Ey, eyespots; Gp, genital papilla; Ll, lower lip; ne, neuropodium; Ul, upper lip. Numbers referring to segments.