Amphitrite edwardsii ( Quatrefages, 1866 )

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 : 11-13

publication ID	https://doi.org/ 10.11646/zootaxa.5038.1.1
publication LSID	lsid:zoobank.org:pub:1C1E4C7A-2452-47BC-B843-2543135EF780
persistent identifier	https://treatment.plazi.org/id/03B887B1-6E3D-FFC0-48F7-624510D19141
treatment provided by	Plazi
scientific name	Amphitrite edwardsii ( Quatrefages, 1866 )
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Treatment

Amphitrite edwardsii ( Quatrefages, 1866)

Figure 3 View FIGURE 3

Terebella edwardsii Quatrefages 1866: 354 View in CoL , pl. XIX, fig. 1.

Amphitrite edwarsii .— Saint-Joseph 1894: 186–198, pl. VII, figs 207–208, pl. VIII, figs 209–223; Fauvel 1927: 245–246, fig. 84, a–h; Jirkov 2020: 329, figs 12–13.

Material examined. MNHN-IA-PNT 125, posteriorly incomplete, Northeastern Atlantic Ocean, Brittany, Bay of Brest , ZE4, 48°17’55”N 4°20’10”W, depth 2 m, June 2016. AM GoogleMaps W.53322, posteriorly incomplete, Northeastern Atlantic Ocean, Brittany, Bay of Brest , ZE4, 48°17’55”N 4°20’10”W, depth 2 m, June 2016 GoogleMaps . MNHN-IA-PNT 126, complete, Northeastern Atlantic Ocean, Bay of Biscay , Pertuis Breton, B 29, 46°17’33”N 1°30’57”W, depth 31 m, September 2007. AM GoogleMaps W.53323, posteriorly incomplete, Northeastern Atlantic Ocean, Bay of Biscay , Pertuis Breton, B 39, 46°15’37”N 1°24’59”W, depth 17 m, September 2007 GoogleMaps .

Description. Large specimens, with complete one being 156.4 mm long and 9 mm wide, for about 112 segments.

Prostomium at base of upper lip, eyespots absent, distal part forming shelf-like tentacular membrane from which numerous filiform and deeply grooved buccal tentacles originate ( Fig. 3A–C View FIGURE 3 ). Peristomium forming lips; upper lip thick, hood-like, convoluted, broader than high; lower lip swollen, broader than high ( Fig. 3C View FIGURE 3 ). Segment I partially hidden by lobes of SG II, forming protruding lobe below lower lip ( Fig. 3C–D View FIGURE 3 ). Segments II–IV with lateral lobes; SG II with small lobes, connected ventrally; SG III–IV with well-developed auricular lateral lobes, more dorsal on SG IV ( Fig. 3C–D View FIGURE 3 ).

Three pairs of dichotomous branchiae, on SG II–IV, with wide medial gap ( Fig. 3B View FIGURE 3 ); second pair inserted more laterally than first and third pairs; with numerous filaments, arising from long annulated stems ( Fig. 3A–D View FIGURE 3 ). Dorsum of anterior chaetigers tessellated ( Fig. 3B View FIGURE 3 ). Nine ventral shields, rectangular to trapezoidal, broader than long, present on SG III–XI, fused on SG II–III ( Fig. 3C View FIGURE 3 ); thereafter shields replaced by mid-ventral groove extending to pygidium (see Morphological variation section).

Notopodia short, rectangular, present on SG IV–XX. Notochaetae slightly curved, medially winged, with wings of same width, and distally serrated; two rows of chaetae, with anterior row about half as long as those on posterior row ( Fig. 3E–F View FIGURE 3 ).

Neuropodia from SG V, with uncini arranged in single rows on SG V–X, uncini in double rows on SG XI–XX, in a face-to-face arrangement, and in single rows again afterwards; thoracic neuropodia as low ridges ( Fig. 3A, C–D View FIGURE 3 ), situated latero-ventrally, some neuropodia with undulating margin (see Morphological variation section) ( Fig. 3D View FIGURE 3 ); abdominal neuropodia raised from the body and displaced more laterally. Uncini avicular, with short triangular heel, distally pointed prow, pointed dorsal button inserted at about halfway between base of main fang and tip of prow, slightly convex base; and crest with four rows of secondary teeth above a distally pointed main fang ( Fig. 3G View FIGURE 3 ).

Nine pairs of nephridial and genital papillae present on SG III–XI ( Fig. 3A View FIGURE 3 ), with first pair situated above LL2 (not seen in Fig. 3A View FIGURE 3 ); second pair above LL3; third pair between LL4 and first notopodia, posteriorly; subsequent pairs between noto- and neuropodia. Nephridial papillae (on SG III–V) elongated, with first one the longest, clearly geniculate, small and globular genital papillae from SG VI–XI ( Fig. 3A View FIGURE 3 ).

Pygidium rounded, slightly crenulated.

Morphological variations. The presence of a ventral groove following the ventral shields seems to be dependent on the fixation process. Indeed, this groove is present and well marked on specimens from the Pertuis Charentais, but absent on specimens from Brittany. Similarly, the presence of undulating margins of neuropodia could be also linked to the fixation process, as they are not present on all specimens observed.

Type locality. Saint-Vaast (Normandy, France), approx. 49°35’45”N 1°15’50”W GoogleMaps .

Type material. The single type specimen available was lost, according to Quatrefages (1866).

Distribution. Bay of Biscay ( Saint-Joseph 1894, this study) ( Fig. 1 View FIGURE 1 ), English Channel ( Saint-Joseph 1898), Ireland, Arctic Sea ( Fauvel 1927), from Scotland to Portugal ( Jirkov 2020), Mediterranean Sea, Adriatic Sea, Aegean Sea, Gulf of Mexico, Puget Sound, Japan ( Gil 2011), Falkland Islands, British Columbia ( Jirkov 2020). As proposed by Jirkov (2020), all records outside southern boreal Europe should be considered as doubtful.

Habitat. Mud to muddy sands (this study; Fauvel 1927; Gil 2011), in Zostera meadow ( Fauvel 1927; Gil 2011), shallow waters to 30 m (this study; Gil 2011).

Remarks. Quatrefages (1866) described this species based on a single specimen, collected at low tide at Saint- Vaast (Normandy, France). Unfortunately, the holotype was lost during its study and the description was sparse and incomplete and incomplete. According to Quatrefages, the most notable characteristic is the position of the branchiae, with the second pair being positioned more laterally than the first and third pairs, giving the appearance of a “star” when seen dorsally ( Fig. 3B View FIGURE 3 ; see also Quatrefages 1866: pl. XIX, fig. 1). As for many species of Terebellidae described in the 19 th century, characters now known to be important were not described, and a neotype needs to be designated in the future, and ideally with associated molecular data.

French specimens match the specimens studied by Jirkov (2020) from Ireland and Orkney, although his description is relatively short and lacks details about the position of the branchiae. The only difference concerns the size and shape of the nephridial papillae being described as longer and the first one clearly geniculate in the French specimens instead of being all of the same size.