Polycirrus pennarbedae Lavesque & Hutchings & Daffe & Londoño-Mesa 2020, n. sp.
Creators: name: Lavesque, Nicolas
name: Hutchings, Pat
name: Daffe, Guillemine
name: Londoño-Mesa, Mario H.
Publisher: name: Zenodo
Year: 2020
Subjects: Biodiversity
Taxonomy
Animalia
Annelida
Polychaeta
Terebellida
Terebellidae
Polycirrus
Polycirrus pennarbedae

description: Polycirrus pennarbedae n. sp.
Figures 16–17, Table 2.
Material examined: Holotype: MNHN-IA-TYPE 2018, one complete specimen, NE Atlantic, Bay of Biscay, Glenan, 47°44’06”N, 4°0’01”W, 7 m depth, March 2015. Paratypes: AM W.53123, one complete specimen, NE Atlantic, Bay of Biscay, Glenan, 47°43’43”N, 3°58’04”W, 5 m depth, March 2015. AM W.53124, one complete specimen, NE Atlantic, Bay of Biscay, Bay of Brest, 48°18’57”N, 4°22’40”W, 2 m depth, May 2017, mounted for SEM.
Additional material: MNHN-IA- PNT 122, one complete specimen, NE Atlantic, Bay of Biscay, Morlaix Bay, 48°42’44”N, 3°57’04”W, 4 m depth, February 2016. MNHN-IA- PNT 123, one complete specimen, NE Atlantic, Bay of Biscay, Morlaix Bay, 48°42’40”N, 3°57’03”W, 4 m depth, February 2016. AM W.53125, one complete specimen, NE Atlantic, Bay of Biscay, Morlaix Bay, 48°42’40”N, 3°57’03”W, 4 m depth, February 2016.
Description. Small species, holotype 11.5 (7.2–10.0) mm long and 0.7 (0.5–1.0) mm wide.
Transverse prostomium attached to dorsal surface of base of upper lip; basal part as thick crest across dorsum, extending laterally and dorsally, covering SG1 laterally and terminating lateral to lower lip. Buccal tentacles of two types, thin tentacles uniformly cylindrical, long and thick ones deeply grooved (Fig. 16C). Peristomium forming lips; upper lip elongate, longer than wide, triangular shape, comprising medial lobe only, very convoluted (Figs 16 A–C; 17A); lower lip oval and inflated, wider than long, very glandular and ridged (Figs 16 A–B; 17A).
SG1 and 2 reduced, SG1 visible dorsally, SG2 dorsally and laterally; body slightly broader until SG6, then of relatively uniform width until mid-body, posterior end tapering (Fig. 16A). Ventro-lateral inflated pads present from SG3 to SG10, smooth (Figs 16 A–C; 17A). Anterior mid-ventral groove present until end of body as a stripe, shallow and narrow between anterior ventral shields (Figs 16 A–C; 17A).
Notopodia from SG3, extending for 12 (13) segments, until SG14 (SG15); distinctly elongate, rectangular, first two pairs slightly shorter, bilobed, postchaetal lobe digitiform, larger than prechaetal one (Fig. 17B). Narrowly winged notochaetae of two different lengths, with wings inconspicuous under light microscopy (Figs 16E; 17 B–C). Neuropodia beginning from SG15 (SG16); uncini with short occipitum and slightly convex base (Type 1) and with a very long prow (Fig. 16F), crest with single elongate and sharp tooth on first row above main fang, with two additional rows of shorter, irregularly sized teeth at base (Fig. 17D), absence of subrostral process (Fig. 16F).
Nephridial and genital papillae not seen.
Pygidium rounded with ventral pointed tip.
Etymology. The species name was chosen by V. Le Garrec who sent us the type material. It refers to Penn-Ar-Bed which is the Breton name for Finistère (Finis Terrae in latin), the French department situated on western part of Brittany. The term “ pennarbedae ” is the genitive of the noun “Penn-Ar-Bed”.
Habitat. Coastal maerl (rhodolith) beds in 2–7 m depth.
Type locality. Glenan archipelago, Bay of Biscay, NE Atlantic Ocean, France.
Distribution. Bay of Biscay (Glenan archipelago, Bay of Brest), English Channel (Morlaix Bay).
Remarks. Polycirrus pennarbedae n. sp is characterized by 12–13 pairs of notopodia and neuropodia starting from SG14–15, which is similar to P. medusa (12 segments with notopodia, neuropodia from SG15), P. latidens (12 segments with notopodia, neuropodia from SG14) and P. catalanensis (13–15 segments with notopodia, neuropodia from SG15–17) (Table 2).
Polycirrus pennarbedae n. sp. differs from P. medusa by the presence of a triangular upper lip with elongated median lobe (instead of trefoiled upper lip for P. medusa), the presence of a lower lip oval, wider than long (instead of upper lip subtriangular and pointing towards the mouth), by the presence of one type of notochaetae (instead of two types for P. medusa) and the ventro-lateral pads not separated by a large mid-ventral groove (large mid-ventral groove on anterior segments for P. medusa) (Table 2).
Polycirrus pennarbedae n. sp. differs from P. latidens by having a narrow and shallow mid-ventral groove between ventro-laterals pads (instead of a well-defined mid-ventral groove present from SG4 for P. latidens), the presence of a lower lip oval (instead of oblong lower lip P. latidens). Polycirrus latidens is also characterized by uncini with teeth above main fang, arranged in single vertical series (instead of crests of teeth as present in P. pennarbedae) (Table 2).
Finally, P. catalanensis n. sp. differs from P. pennarbedae n. sp. by the shape of uncini (two rows of teeth above the main tooth for P. pennarbedae n. sp., a single row of secondary teeth above the main tooth for P. catalanensis n. sp.), the shape of upper lip (elongated triangular medial lobe for P. pennarbedae n. sp., in contrast a very thick single medial lobe present in P. catalanensis n. sp.), the shape of lower lip (oval and wider than long for P. pennarbedae n. sp., rectangular and longer than wide P. catalanensis n. sp.) and the presence of a large mid-ventral grove on anterior segments for Polycirrus catalanensis n. sp. (narrow and shallow for P. pennarbedae n. sp.) (Table 2).
description: Published as part of Lavesque, Nicolas, Hutchings, Pat, Daffe, Guillemine & Londoño-Mesa, Mario H., 2020, Revision of the French Polycirridae (Annelida, Terebelliformia), with descriptions of eight new species, pp. 151-186 in Zootaxa 4869 (2) on pages 174-177, DOI: 10.11646/zootaxa.4869.2.1, http://zenodo.org/record/4418481