taxonID	type	description	language	source
03A187E0FFC4FFC0FF23841AFEF2FA8A.taxon	type_taxon	Type species: Amphitrite cirrata Müller, 1776, by subsequent designation	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	description	Figures 2 and 3	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	materials_examined	Material examined. MNHN-IA- 2017 - 2211, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, Grande Miquelon Lake, 47.092622 ° N, 56.368040 ° W, intertidal, October 2023, one complete specimen, some parapodia used for molecular analysis. AM W. 55317, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, Saint-Pierre Harbour, 46.776196 ° N, 56.163452 ° W, intertidal, October 2023, one complete specimen, some parapodia used for molecular analysis, specimen mounted for SEM.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	description	Description. Large-sized species with longest specimen 147.8 mm long and 11.4 mm wide, for about 112 segments. Prostomium at base of upper lip, without eyespots, distal part forming shelf-like tentacular membrane from which filiform, wrinkled and deeply grooved buccal tentacles originate (Figs 2 A – C; 3 A). Peristomium forming lips; upper lip thick, hood-like, convoluted, broader than high; lower lip swollen, broader than high (Fig. 2 C). Segment I clearly visible, forming protruding lobe below lower lip (Fig. 2 C). Segments II – III with small ventro-lateral lobes, SG IV with very small dorsal lobes, situated anteriorly and ventrally from the notopodia (Figs 2 A; 3 B). Three pairs of dichotomous branchiae, on SG II – IV, with wide medial gap; second pair inserted more laterally than first and third pairs; with numerous strongly annulated filaments, arising from short stems (Figs 2 A – B; 3 A). Dorsum of anterior chaetigers tessellated (Figs 2 B; 3 A). Thirteen-fourteen ventral shields, rectangular, broader than long, present on SG III – XV (Fig. 2 C); absence of mid-ventral groove. Notopodia short, rectangular, present on SG IV – XXVIII (n = 25), one specimen with 24 notopodia on one side and 25 on the other one. Notochaetae almost straight, medially winged with wings of same width, and distally serrated; two rows of chaetae, those of anterior row less than half as long as those of posterior row (Fig. 3 B). Neuropodia beginning from SG V, with uncini arranged in single rows on SG V – X, uncini in double rows on SG XI – XXIX (second abdominal chaetiger), in a face-to-face arrangement, and in single rows again from SG XXX. One specimen with second abdominal neuropodia with uncini in double row dorsally, and in a single row ventrally. Thoracic neuropodia as low ridges, situated latero-ventrally (Figs 2 A, C, 3 A – B); abdominal neuropodia raised from body and displaced more laterally (Figs 2 D, 3 E). Uncini avicular, with short triangular heel, with distally pointed prow, large pointed to digitiform dorsal button inserted halfway between base of main fang and tip of prow, convex base; and crest with five rows of secondary teeth above main fang (Fig. 3 A – D). Seventeen pairs of very small nephridial and genital papillae present on SG III – V and VI – XIX respectively (Figs 2 A; 3 A – B), first pair larger than the following ones, situated above base of second pair of branchiae, second pair below first notopodia and slightly displaced dorsally, subsequent pairs between noto- and neuropodia, slightly displaced dorsally, last pairs difficult to see. Pygidium rounded and slightly crenulated (Fig. 2 D).	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	materials_examined	Type locality. Probably North Sea coast of Scotland (Gil 2011). Type material. Could not be traced (Holthe 1986, Jirkov 2020).	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	distribution	Distribution. Amphitrite figulus is present in Europe from the Norwegian Sea to the Aegean Sea (Gil 2011, Jirkov 2020, Lavesque et al. 2021 a), and in Canada (Carr et al. 2011). This species is also reported from the North Atlantic, Arctic, North Sea, western Baltic (Hartmann-Schröder 1996), Japan, the Gulf of Mexico and the Sea of Okhotsk (Gil 2011) but all of these records should be regarded as doubtful, at least until molecular data are provided. Indeed, documenting species distributions using morphology alone has led to the popularization of the cosmopolitan species concept and a clear underestimation of biodiversity (Hutchings & Kupriyanova 2018; Lavesque et al. 2019 b; Hutchings & Lavesque 2020).	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	biology_ecology	Habitat. This species lives in empty shells in deep water, and among rocks in shallow intertidal pools, on mud or sandy mud, among Zostera, Fucus or Laminaria, on mussel and oyster banks (Gil 2011), in mud (Lavesque et al. 2021 a), in silted heterogeneous sediments in semi-enclosed lagoon (this study), in coarse gravels and shells (Hardy et al. 2011) from 20 m to intertidal (Hardy et al. 2011, Jirkov 2020, Lavesque et al. 2021 a, this study). In the original description, Dalyell (1853) considers this species to be an architect and calls it the “ potter ”. The worm selects mud or clay exclusively for the materials for its tube, which is thick and clumsy.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC4FFCFFF2384C6FFB4F82E.taxon	discussion	Remarks. As previously highlighted by Lavesque et al. (2021 a), the species is poorly described in the original description which does not include important characters useful for the taxonomy of this genus. The specimens examined in this study match those of the French coasts (Lavesque et al. 2021 a), even if several morphological differences occur. Indeed, specimens observed from the French coasts were much smaller (48 mm) than specimens observed during this study (148 mm). Probably linked to the size of specimens, the number of genital papillae is higher in Saint-Pierre and Miquelon specimens (n = 17) than in Normandy (n = 15). Another difference concerns the presence of small lobes on SG 4 in some of the SPM specimens which are absent in specimens from Normandy. After re-examination of the specimen MNHN-IA-PNT 127, the right side shows a small lobe on SG 4 (which is more difficult to observe on the left side, as illustrated in the Fig. 4 in Lavesque et al. 2021 a). This lobe is also difficult to see on the specimen from St Pierre and Miquelon used for SEM (Fig. 3 B). Jirkov (2020), who observed European specimens, also noted the presence of these small lobes on SG 4. Morphological differences between small and large specimens of terebellid species have already been observed (Martin et al. 2022; Hutchings et al. 2025). The molecular analyses showed that Amphitrite figulus has a very wide distribution in the North Atlantic (Fig. 4 A). However, genetic differences have been observed between specimens sampled in the north-east Atlantic (France, Ireland, Russia, Norway) and those sampled in the west (Canada) (Fig. 4 B). More diversity is found in the Western Atlantic with four different haplotypes found whereas only one was found in the Eastern Atlantic. The genetic distances observed between the two populations (between 2.5 and 3 %) could indicate that these populations belong to a single species with limited geneflow between populations. Large intraspecific distances in COI have previously been observed in polychaetes (e. g. Nygren et al. 2018) and are compatible with the large geographic distance between both populations. Alternatively, the two populations could represent different species. Recent speciation would explain the comparatively low interspecific distances. To test these hypotheses, new specimens need to be sampled in the geographical transition zones between the east and west of the Atlantic Ocean. In particular, it would be very interesting to obtain sequences of individuals from Greenland. At present, we conservatively consider both populations as belonging to a single species, but future studies will confirm or deny this hypothesis and more detailed genetic analyses must be performed.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFCCFF2385B8FEDBFAE5.taxon	type_taxon	Type species. Thelepus cincinnatus (Fabricius, 1780) by original designation.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	description	zoobank. org: act: 6483 B 533 - 7 FE 5 - 4 DF 5 - 9896 - 22 D 6 C 3 B 5 A 664 Figures 5 and 6	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	materials_examined	Material examined. Holotype. MNHN-IA- 2000 - 2102, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, West of Saint-Pierre Island, SPM 32, 46.771292 ° N, 56.307388 ° W, 46 m depth, September 2023, complete, some parapodia used for molecular analysis. Paratypes. AM W. 55318, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, East of Saint-Pierre Island, SPM 4, 46.805247 ° N, 56.115607 ° W, 100 m depth, September 2023, complete, some parapodia used for molecular analysis, mounted for SEM. MNHN-IA- 2000 - 2103, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, SW of Saint-Pierre Island, SPM 30, 46.732683 ° N, 56.271452 ° W, 80 m depth, September 2023, incomplete, some parapodia used for molecular analysis. MNHN-IA- 2000 - 2104, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, SW of Saint-Pierre Island, SPM 30, 46.732683 ° N, 56.271452 ° W, 80 m depth, September 2023, complete, some parapodia used for molecular analysis. MNHN-IA- 2000 - 2105, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, East of Saint-Pierre Island, SPM 4, 46.805247 ° N, 56.115607 ° W, 100 m depth, September 2023, complete, gravid. Additional material. SMA-NL 272, North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago, SW of Saint-Pierre Island, SPM 30, 46.732683 ° N, 56.271452 ° W, 80 m depth, September 2023, some parapodia used for molecular analysis.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	description	Description (based on holotype and paratypes). Holotype complete (about 110 segments), 91.6 mm long, 3.3 mm wide. Largest paratype (MNHN-IA- 2000 - 2105) 145 mm long and 4 mm wide. Prostomium at base of upper lip; numerous black eyespots in continuous dark band, with 3 – 4 irregular rows (Fig. 5 B); buccal tentacles long, thick, deeply grooved (Figs 5 A – D; 6 A – B). Upper lip as wide as long, striated, thick, hood-like (Fig. 5 D); lower lip thick, wider than long, striated, surrounded by ventral crescent-shaped lobe originating from SG 1 (Fig. 5 D). SG 1 and SG 2 short, visible laterally and dorsally (Fig. 5 B). Two pairs of branchiae, on SG 2 – 3, with 10 – 21 filaments on SG 2 and 6 – 13 on SG 3 (Figs 5 B – C; 6 A – B); filaments short, distally blunt, cylindrical, arising directly from body wall, with wide medial gap; branchial filaments arranged in two irregular rows (Fig. 5 C). First pair of branchiae situated more laterally. Ventral surface of anterior segments strongly glandular, corrugated on anterior-most segments, ventral shields absent (Fig. 5 D); thin mid-ventral stripe beginning from about SG 29 – 30. Notopodia from SG 3 to almost the end of the body, present on holotype from SG 3 to SG 97 (for about 110 segments), on paratype MNHN-IA- 2000 - 2104 from SG 3 to SG 70 (for about 85 segments) and from SG 3 – 84 (for about 90 segments) for paratype MNHN-IA- 2000 - 2105; notopodia short, roughly rectangular, distally rounded (Figs 5 B – C; 6 A – B); notochaetae emerging between lobes. Few falcate notochaetae in both rows, anterior row with about 10 twisted winged chaetae (Fig. 6 C), posterior row with about eight narrowly-winged notochaetae (Fig. 6 C); well-marked difference in length between rows (Fig. 6 C). Neuropodia from SG 5, as long fleshy ridges on anterior body, progressively shorter and more raised from midbody segments onwards (Figs 5 E; 6 D – E). Uncini with terminal dorsal button, short prow, much shorter than button, base curved; uncini longer than high (Fig. 6 G). Crest of uncini with three rows of secondary teeth, basal row with 2 – 3 teeth, second row with 1 – 2 teeth, last row with irregularly sized teeth (Fig. 6 F). Nephridial and genital papillae not seen. Pygidium with 5 – 6 globular papillae (Fig. 5 E). Tube incrusted with gravels, foraminifera and shell fragments.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	etymology	Etymology. This species is dedicated to Jean Recher, a fishing captain from the days of great fishing on the banks of Newfoundland who wrote the book “ Le Grand Métier ” (“ The Great Profession ”). He probably dredged up many specimens of this new species.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	materials_examined	Type locality. North Atlantic Ocean, Saint-Pierre and Miquelon Archipelago.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	distribution	Distribution. Canadian region: Saint-Pierre and Miquelon Archipelago (this study), New Brunswick (Dewaard unpub; Carr et al. 2011 as T. cincinnatus in GenBank), Newfoundland and Labrador (Carr et al. 2011, as T. cincinnatus in GenBank) (Fig. 8; Table 2).	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	biology_ecology	Habitat. Between 46 and 100 m depth, pebbles with coralline crusts (rhodoliths), rocky substrate.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
03A187E0FFC8FFC9FF238464F860FCE6.taxon	discussion	Remarks. Only two species of Thelepus have been described from the NW Atlantic: T. abranchiatus (Hartman & Fauchald, 1971) and T. cincinnatus (Fabricius, 1780). The holotype of T. abranchiatus was re-examined by Hutchings & Glasby (1986). This last species differs mainly from Thelepus recheri n. sp. in the absence of branchiae, which are well developed in T. recheri n. sp. and in the number of notochaetae, which are present on 30 pairs of notopodia and 60 % of the body length for T. abranchiatus and about 90 notopodia and until the end of the body in T. recheri n. sp. In addition, T. recheri n. sp. is a coastal species that lives at depths of between 50 and 100 m, while T. abranchiatus is a deep-water species sampled at 2022 m (Hutchings & Glasby 1986). Thelepus recheri n. sp. has probably been confused with the so-called cosmopolitan species T. cincinnatus, as for example in Carr et al. (2011) (Fig. 8). Indeed, this last species has been described from western Greenland which is only separated from SPM by the Labrador Sea and is largely reported in the Canadian region. Recently, Nogueira (2019) redescribed T. cincinnatus based on syntypes from the type locality (= “ Torell’ topotypes ”). Based on morphological characters, the two species can easily be distinguished from each other. The branchiae of T. recheri n. sp. are separated by a wide medial gap which is inconspicuous for T. c incinnatus. The mid-ventral groove begins from SG 10 for T. cincinnatus and from about SG 30 for T. recheri n. sp. The notopodia of T. recheri n. sp. are present almost until the end of the body while they terminate far from the posterior end for T. cincinnatus. In the Northern hemisphere, another species has two pairs of branchiae, the presence of eyespots and notopodia until the end of the body: T. parapari Jirkov 2018, described from the Mediterranean Sea. However, T. recheri n. sp. differs by the presence of black eyespots instead of red ones (which are rarely present), by the higher number of branchial filaments (up to 21 filaments for the first branchiae and up to 17 for the second ones for T. recheri n. sp., instead of 11 and 8 filaments respectively for T. parapari), and by the shape of the pygidium which presents 5 – 6 globular papillae for T. recheri n. sp. and which is crenulated for T. parapari. The notochaetae of T. parapari are usually in one row with mixed short and long chaetae while there are always two rows for T. recheri n. sp. with well-marked difference in length between rows. The posterior uncini of T. parapari have only one row of tooth / teeth above the main fang (“ uncini have only one tooth in profile ”) while there are always two rows above the main fang for T. recheri n. sp. Finally, the two species are found in two very different habitats with T. recheri n. sp. found up to 100 m depth in a sub-Arctic region and T. parapari present in the Mediterranean Sea up to 15 m depth. The molecular results allow us to confirm the presence of T. recheri n. sp. in several localities in Canada. The intraspecific distances (K 2 P) between the SPM specimens and the Canadian specimens observed are 0 % for both COI and 16 S. The 16 S sequences of T. recheri n. sp. are very different (K 2 P: 7.6 %) from a sequence of T. cincinnatus from Trondheim in Norway (GenBank accession number DQ 779636, Fig. 7) (Rousset et al. 2007), but once again we have no certainty that this has been correctly identified. The type species of the genus, Thelepus cincinnatus (Fabricius, 1780), has long been considered as a cosmopolitan species with a worldwide distribution. The democratisation of molecular tools has led to major advances in our understanding of geographical distributions and has highlighted that many cosmopolitan species are actually complexes of cryptic or pseudo-cryptic species (Nygren et al. 2018; Hutchings & Lavesque 2020; Lavesque et al. 2021 b). It is now accepted that such a wide distribution and variety of habitats, as for T. cincinnatus, is unlikely. Recently, Jirkov redescribed T. cincinnatus but while he used almost 2000 specimens from more than 100 stations, none of these stations were from the type locality, but instead covered a wide range of depths (2 to 2000 m), from the Arctic to the Mediterranean (Jirkov, 2018). To confirm his identification, he compared his specimens with Pettibone’s description of topotypes (Pettibone 1954). However, Pettibone used a large number of specimens for her description, with animals collected from both the Beaufort Sea, the east and west coasts of the USA and the type locality (eastern Greenland), and no topotype was formally established as a name-bearing type. However, with such a wide geographical distribution, it is possible that she was dealing with several different species. Finally, in 2019, Nogueira was able to examine specimens of T. cincinnatus stored in the Naturhistoriska Riksmuseet (Swedish Museum of Natural History) in Stockholm, Sweden. Three specimens (NRM 84944) “ which apparently were intended to be designated as syntypes, as the lot is labelled as ‘ Type 1270 ’ in the museum’s old catalogue, but that never happened ” (Nogueira 2019). These specimens were collected by O. Torell in 1859, almost 80 years after the original description (Fabricius 1780), at the same locality as the worms studied by Fabricius (Nogueira, 2019). These “ Torell’ topotypes ” and their precise description, permitted us to confirm that specimens from SPM belong to a different, undescribed, species: Thelepus recheri n. sp.	en	Lavesque, Nicolas, Pinsivy, Lucas, Daffe, Guillemine, Daramy, Flore, Grosse, Maël, Chauvaud, Laurent, Hutchings, Pat (2025): A new species of the Thelepus cincinnatus complex from Saint-Pierre and Miquelon Archipelago (NW Atlantic) and genetic diversity of Amphitrite figulus (Dalyell, 1853) (Annelida, Terebelliformia). Zootaxa 5588 (2): 250-268, DOI: 10.11646/zootaxa.5588.2.3, URL: https://doi.org/10.11646/zootaxa.5588.2.3
