Perinereis hourdezi, Salazar-Vallejo & León-González, 2025

Salazar-Vallejo, Sergio I. & León-González, J. Angel De, 2025, Additional new species of marine annelids from Clipperton Island (Nereididae: Pilargidae: Sabellariidae), European Journal of Taxonomy 1026, pp. 1-29 : 4-10

Perinereis hourdezi sp. nov.

urn:lsid:zoobank.org:act:

Fig. 1

Diagnosis

Perinereis with posterior eyes completely exposed; tentacular belt 1.4× as long as first chaetiger; longest tentacular cirri reaching chaetigers 6–11; jaws with 3–5 teeth; pharyngeal area VI with shield-shaped bars, areas VII–VIII with 21–26 paragnaths in three transverse rows; posterior parapodia with enlarged glandular masses along dorsal ligules bases.

Etymology

The species is named after Dr Stéphen Hourdez in recognition of his contributions on polychaetes, especially of those of hydrothermal vents, and because he participated in the expedition to Clipperton Island and collected part of the specimens for describing this species.

Type material

Holotype

FRANCE • mature ♀ (complete spec.); Clipperton Island , stn 33; 10°18.27′ N, 109°14.00′ W; depth 1 m, platform; 25 Jan. 2005; L. Albenga and L. Dugrais leg.; MNHN IA-2000-2107 .

Paratypes

FRANCE • 3 ♀♀ (1 complete and 2 incomplete specs); Clipperton Island , stn 33; 10°18.27′ N, 109°14.00′ W; depth 1 m, platform; 25 Jan. 2005; L. Albenga and L. Dugrais leg.; UANL 8292 • 3 ♀♀ (1 complete and 2 incomplete specs); Clipperton Island , stn 33; 10°18.27′ N, 109°14.00′ W; depth 1 m, platform; 25 Jan. 2005; L. Albenga and L. Dugrais leg.; ECOSUR 317 • 8 ♂♂ (5 complete and 3 incomplete specs); Clipperton Island , stn 27; 10°18.01′ N, 109°13.87′ W; depth 1 m, platform; 23 Jan. 2005; S. Hourdez and K.-L. Kaiser leg.; in front of Camp Bougainville; ECOSUR 318 .

Description ( holotype)

BODY. Mature female, complete, subcylindrical; 43 mm long, 2 mm wide (without parapodia), 111 chaetigers. Dorsum yellowish, with two light brown lateral lines along body, and a pale middorsal line along 51 chaetigers, thereafter brownish to body end. Venter homogeneously yellowish.

PROSTOMIUM. Slightly longer than wide; two pairs of eyes in trapezoidal arrangement, gap between both pairs 1.3 × as wide as diameter of posterior pair. Anterior pair in lateral position, oval, with eye diameter as wide as antennae basal diameter, with gap between eyes 6 × as wide as eye diameter; lenses visible, reddish, rounded, placed anterolaterally covering about 80% of eye. Posterior pairs rounded, blackish, minute, about 1 /20 as wide as prostomial width, with diameter 3 × as wide as that of antennae basis, not covered by tentacular belt; with gap between eyes 9 × as wide as eye diameter. Palpophores longer than wide, palpostyle rounded. Median notch extended to middle of prostomium, to level of anterior pairs of eyes.

TENTACULAR BELT. 1.4 × as long as first chaetiger; anterior margin not covering posterior eyes. Tentacular cirri corrugate to articulate, tips of two right lateral cirri broken, posterior dorsal cirri reaching chaetiger 6 ( Fig. 1A).

ANTENNAE. Conical, tapering, wider basally, tips not reaching palpophore ends, 3.3 × as long as wide at basal region; antennae separated by space as wide as half basal diameter of antennae.

PHARYNX. Not exposed, ventrodistal incision needed. Jaws amber with 5 accessory denticles. Paragnaths light brown in color, consisting of uniform-base cones, except shield-shaped bars on Area VI, those of maxillary ring smallest. Formula as follow: maxillary ring: paragnaths conical. AI = 2 in a line; AII = 4 left, 6 right; AIII = 7 paragnaths in central group, and a pair of paragnaths in a line at each side; AIV = 8 left, 10 right. Oral ring: paragnaths conical and smooth bars. AVI-V-VI pattern, υ-shaped (after Villalobos-Guerrero, 2019); AV = 3 conical paragnaths in inverted triangle; AVI= one long shield-shaped bar to each side; VII–VIII = 24 paragnaths with wide basis in three regular bands, anterior band consisting of seven paragnaths only in ridge position, middle band with 11 cones in furrow and ridge, posterior band with six on each ridge position.

CHAETIGERS 1–2. With neuraciculae only; with both noto- and neuraciculae thereafter.

NOTOPODIA. Consisting of dorsal cirrus (comprising proximal cirrophore and distal cirrostyle), dorsal ligule, and median ligule in biramous parapodia.

ANTERIOR PARAPODIA ( FIG. 1C). Dorsal cirrophore with two light brown glandular areas, proximal one smaller. Dorsal cirrostyle longer than dorsal ligule, 1.5 × as long as ventral cirri. Dorsal ligule triangular, with blunt tip, 1.4 × as long as wide. Median ligule subconical, blunt, 1.4 × as long as wide, similar size to dorsal ligule. Neuroacicular ligule with superior lobe shorter than inferior lobe, both blunt. Neuropodial prechaetal lobe missing, postchaetal one present. Ventral ligule subconical, 3 × as long as wide, slightly longer than ventral cirri. Notochaetae 5 homogomph spinigers. Supracicular neurochaetae 5 homogomph spinigers, and 3 heterogomph falcigers with blunt tips and spinulose inner edge, blade 6 × as long as wide ( Fig. 1F). Infracicular neurochaetae 1 heterogomph spiniger and 11 heterogomph falcigers, similar than supracicular ones, decreasing slightly in size towards ventral part.

MEDIAN PARAPODIA ( FIG. 1D). Dorsal cirrophore with four glandular patch, proximal one smaller, rounded, distal one larger. Dorsal cirrostyle 1.7 × as long as dorsal ligule. Dorsal ligule triangular, tapered, 1.6 × as long as wide, with elongated glandular area. Median ligule subconical, blunt, 2 × as long as wide, slightly longer than dorsal ligule. Neuroacicular ligule rounded anteriorly, with superior lobe slightly visible. Neuropodial prechaetal lobe missing, postchaetal one present. Ventral ligule subulated, 2.5 × as long as wide, slightly longer than ventral cirri. Notochaetae 7 homogomph spinigers. Supracicular neurochaetae 5 homogomph spinigers and 1 heterogomph falcigers, blade 5 × as long as wide; infracicular neurochaetae 1 homogomph spiniger and 7 heterogomph falcigers, blade 5.2 × as long as wide ( Fig. 1G).

POSTERIOR PARAPODIA ( FIG. 1E). Dorsal cirrophore with two dark fused glandular areas. Dorsal cirrostyle 1.5 × as long as dorsal ligule, inserted medially. Dorsal ligule triangular, tapered, 1.8 × as long as wide, enlarged glandular masses covering base of ligule. Median ligule subconical, blunt, 2.5 × as long as wide, larger than dorsal one. Neuroacicular ligule triangular, longer than wide. Neuropodial prechaetal lobe missing, postchaetal one present. Superior and inferior lobes not seen; ventral ligule subtriangular, tapered, 2.9 × as long as wide. Ventral cirri similar in size to ventral ligule. Notochaetae 4 homogomph spinigers. Supracicular neurochaetae 6 homogomph spinigers and 2 heterogomph falcigers one of them broken, blade 5.6 × as long as wide ( Fig. 1H). Infracicular neurochaetae 1 heterogomph spiniger, and 4 heterogomph falcigers, blades 6 × as long as wide ( Fig. 1I).

POSTERIOR REGION. Pygidium with terminal anus and pair of long anal cirri, as long as last 4–5 chaetigers ( Fig. 1B).

OOCYTES. Brownish, only present in posterior parapodia, each about 90 µm in diameter, distorted inside right margin of Fig. 1E.

Variation

Complete paratypes are 35–60 mm long, 1.2–2.2 mm wide, with 100–114 chaetigers. A specimen with one paragnath on Area I, another specimen with 3 paragnaths in a line, all other specimens with 2 paragnaths in a line; Area II with 6 paragnaths in two lines in all specimens in each side; Area III with a central group of 8 to 12 small paragnaths and one or two paragnaths on each side. Area IV with 10–11 paragnaths at right side and 10–12 at left side; Area V invariably with three large paragnaths in inverted triangle; Area VI with one large bar on each side, except in two specimens in one of them, the left bar was fragmented into two pieces. Longer tentacular pair of cirri reaching chaetigers 7–11.

Distribution

This species is known only from Clipperton Island.

Remarks

The original proposal of the species group of Perinereis by Hutchings et al. (1991) was modified by Prajapat et al. (2024), by transferring 10 species from group 1B to group 1A without giving arguments; the species transferred were P. barbara ( Monro, 1926) from Port Jackson, Australia; P. capensis ( Kinberg, 1865) from Good Hope Cape, South Africa; P. iranica Bonyadi-Naeini, Rastegar-Pouyani, Glasby & Rahimian, 2018 from Iran, Persian Gulf; P. kaustiana Teixeira, Fourreau, Sempere-Valverde & Carvalho, 2024 from Saudi Arabia, Gulf of Aqaba; P. nigropunctata ( Horst, 1924) from Malaysia; P. obfuscata ( Grube, 1878) from Philippines; P. perspicillata ( Grube, 1878) from Philippines; P. pictilis Glasby, Nu- Wei & Gibb, 2013 from Queensland, Australia; P. striolata ( Grube, 1878) from Philippines; P. suluana ( Horst, 1924) from Pulu Tongkil, Sulu Archipielago and P. villabosi Rioja, 1947 from Western Mexico. Except for P. iranica , P. obfuscata , P. perspicillata , P. pictilis , and P. striolata , we prefer to leave the rest of the species in subgroup 1B due to the notable development of the posterior parapodia explained in the descriptions or redescriptions of these species.

Perinereis hourdezi sp. nov. belongs to the informal species group proposed by Hutchings et al. (1991) characterized by having a transverse bar in Area VI, and dorsal cirrophore not greatly expanded (Group 1A); currently there are 27 species considered in this group. The group includes P. arabica Mohammad, 1971 described from Kuwait; P. atlantica (McIntosh, 1885) from Cape Verde Islands; P. calmani Monro, 1926 from Eastern Australia and China Sea; P. cultrifera Grube, 1840 from Naples, Mediterranean Sea; P. falsovariegata Monro, 1933b from Still Bay, South Africa; P. faulwetterae Teixeira, Langeneck, Grosse, Bakken & Ravara, 2025 from the Mediterranean Sea; P. floridana Ehlers, 1868 from Florida, North America; P. helleri Grube, 1878 from the Philippines; P. houbihuensis Hsueh, 2024 from Taiwan; P. iranica Bonyadi-Naeini et al., 2018 from Abu Musa Island, Persian Gulf; P. louizomarum Rezzag Mahcene, Villalobos-Guerrero, Kurt, Denis & Dass, 2023 from Algeria; P. longdongwanensis Hsueh, 2024 from Taiwan; P. minerva Teixeira, Langeneck, Grosse, Bakken & Ravara, 2025 from the Mediterranean Sea; P. misrai Prajapat, Villalobos & Vachhrajani, 2024 , from India; P. muscoi Teixeira, Langeneck, Grosse, Bakken & Ravara, 2025 from the Mediterranean Sea; P. obfuscata ( Grube, 1878) from the Philippines; P. pangcahae Hsueh, 2024 from Taiwan; P. perspicillata ( Grube, 1878) from the Philippines; P. rullieri Pilato, 1974 from Sicily, Catania, Mediterranean Sea; P. pseudocultrifera Hsueh, 2024 from Taiwan; P. seurati Gravier 1905 from Gambier Islands in freshwater; P. striolata ( Grube, 1878) from the Philippines; P. taitungensis Hsueh, 2024 from Taiwan; P. taorica Langerhans, 1881 from the Canary Islands; P. tenuisetis Fauvel, 1915 from the Mediterranean Sea; P. twobae Teixeira, Langeneck, Grosse, Bakken & Ravara, 2025 from the Mediterranean Sea; and P. websteri Conde-Vela 2022 from Bermuda.

Perinereis hourdezi sp. nov. resembles P. cultrifera , P. helleri , P. misrai , P. rullieri , P. taitungensis , P. rullieri , P. taorica and P. websteri by having Area III with 2–3 paragnaths in line on both side of the central area, as well as 3 paragnaths in a triangular arrangement over Area V. However, P. hourdezi as well as P. misrai , P. rullieri and P. websteri do not present notopodial prechaetal lobe; P. hourdezi can be separated from these species because it has a short neuropodial postchaetal lobe on all parapodia.

Solís-Weiss & Hernández-Alcántara (2009: 251, 255) recorded Perinereis sp. for Clipperton Island, after 7 anterior fragments of juvenile specimens collected in their station 2, in the west side of the island. Their specimens could belong to this newly described species, but because it was not illustrated and the specimens were not available, we cannot clarify their status.

Key to the species of group 1A of Perinereis Kinberg, 1865

(after Hutchings et al. 1991, modified by Prajapat et al. 2024)

1. Dorsal cirri short, barely or not protruding beyond distal region of dorsal ligule in mid-body parapodia ........................................................................................................................................... 2

– Dorsal cirri long, protruding distinctly beyond distal region of dorsal ligule in mid-body parapodia ......................................................................................................................................................... 23

2. Notopodial prechaetal lobe present .................................................................................................. 3 – Notopodial prechaetal lobe absent .................................................................................................. 18

3. Neuropodial postchaetal lobe present throughout body ................................................................... 4 – Neuropodial prechaetal lobe absent .................................................................................................. 6

4. Acicula light yellow; Area V without paragnaths; neurochaetae with homogomph falcigers ........... ...................................................................................................... P. tenuisetis ( Fauvel, 1915) ( Italy) – Aciculae dark brown or black; Area V with paragnaths; neurochaetae with heterogomph falcigers .......................................................................................................................................................... 5

5. Areas VII–VIII with four irregular bands of paragnaths; Area III without laterally isolated paragnaths; Area I with 0–2 paragnaths; subacicular neurochaetae with homogomph spinigers .......................... ............................................................................................... P. arabica Mohammad, 1971 ( Kuwait)

– Areas VII–VIII with a line of 3–6 paragnaths; Area III without laterally isolated paragnaths; Area I with 16 paragnaths in group; subacicular neurochaetae with heterogomph spinigers ....................... ............................................................................................... P. taorica Langerhans, 1881 ( Madeira)

6. Area III with laterally isolated paragnaths ........................................................................................ 7 – Area III without laterally isolated paragnaths ................................................................................ 13

7. Area V with paragnaths ................................................................................................................... 8 – Area V without paragnaths .............................................. P. pseudocultrifera Hsueh, 2024 ( Taiwan)

8. Area V with only one paragnaths ...................................................................................................... 9 – Area V with 2 or more paragnaths ...................................................................................................11

9. Area I with one paragnath; Area III with 6–7 paragnaths; Area VI with a shield-shaped bar ............ ............................................. P. minerva Teixeira, Langeneck, Grosse, Bakken & Rava, 2025 ( Italy) – Area I with numerous paragnaths; Area III with more than 10 paragnaths; Area VI with a crescent-shaped bar ....................................................................................................................................... 10

10. Posterodorsal tentacular cirri reaching chaetiger 8.2 × as long as palps; Area I with 4 or more paragnaths ............................................................................. P. striolata ( Grube, 1878) ( Philippines) – Posterodorsal tentacular cirri reaching chaetiger 5, about as long as palps; Area I with 1 paragnath ............................................................................................ P. obfuscata ( Grube, 1878) ( Philippines)

11. Dorsal cirrus subequal or slightly shorter than dorsal ligule in middle parapodia ......................... 12

– Dorsal cirrus slightly longer than dorsal ligule in middle parapodia; notopodial prechaetal lobe present throughout body; posterodorsal tentacular cirri reaching chaetiger 5–8; Area I with one paragnath; Area V with 3 paragnaths in triangle; ridge of areas VI–V–VI with U-shaped pattern .... .................................................................................................... P. rullieri Pilato, 1974 ( Sicily, Italy)

12. Posterodorsal tentacular cirri reaching chaetiger 4–5; jaws with 4–5 teeth; Area VI with conical shield-shaped bar; ridge of areas VI–V–VI with π- shaped pattern .................................................... ....................................................................................................... P. cultrifera ( Grube, 1840) ( Italy) – Posterodorsal tentacular cirri reaching chaetiger 2; jaws with 3 teeth; Area VI with rectangular-shaped type bar; ridge of areas VI–V–VI with ɔc- shaped pattern ...... P. taitungensis Hsueh, 2024 (Taiwan)

13. Postero-dorsal tentacular cirri reaching chaetiger 2–3 ................................................................... 14 – Postero-dorsal tentacular cirri reaching chaetiger 4 ....................................................................... 16

14. Area I with 2 paragnaths in a line; Area V with 0–1 paragnaths; jaws with up to 5 teeth .............. 15 – Area I with 5 paragnaths in group; Area V with 4 (4–16) paragnaths; jaws with up to 3 teeth ......... ...................................................................................... P. longdongwanensis Hsueh, 2024 ( Taiwan)

15. Area V with 1 paragnath; Area VI with a smooth-shaped bar; with neuropodial postchaetal lobe ....................................................................................... P. houbihuensis Hsueh, 2024 (Taiwan) – Area V without paragnaths; Area VI with crescent-shaped bar; without neuropodial postchaetal lobe ................................................... P. calmani ( Monro, 1926) ( Australia and MacClesfield Bank)

16. Posterodorsal tentacular cirri reaching chaetiger 5–6; jaws with up to 6 teeth; Area III with no more than 7 paragnaths ............................................................................................................................ 17

– Posterodorsal tentacular cirri reaching chaetiger 11; jaws with 11 teeth; Area III with 10–15 paragnaths ................................................ P. seurati Gravier, 1905 (Gambier Islands, in freshwater)

17. Jaws with 0–3 teeth; Area V without paragnaths, rarely with 1–2; Area VI with crescent-shaped bar ........... P. louisomarum Rezzag Mahcene, Villalobos-Guerrero Kurt, Denis & Dass, 2023 ( Algeria)

– Jaws with 5–6 teeth; Area V with 3 paragnaths in triangle; Area VI with chevron-shaped bar; ridge of areas VI–V–VI with U-shaped pattern ........................................................................................... .............. P. muscoi Teixeira, Langeneck, Grosse, Bakken & Rava, 2025 ( Italy, Salento, Ionian Sea)

18. Area V with 1 paragnath ................................................................................................................. 19 – Area V with 3 or more paragnaths .................................................................................................. 21

19. Area I with 1 paragnath; Area III without laterally isolated paragnaths ............................................. ................................................................... P. atlantica ( M’Intosh, 1885) ( São Vicente, Cape Verde) – Area I with 2 or more paragnaths; Area III with laterally isolated paragnaths ............................... 20

20. Area I with 2 paragnaths; ridge of areas VI–V–VI with λ-shaped pattern; Area VI with smooth shaped bar ................................................................................... P. floridana Ehlers, (1868) ( Florida, USA)

– Area I with 4 (rarely 2–5) paragnaths; Area VI–V–VI with ɔc- shaped ridge pattern; Area VI with bar type chevron-shaped ................................................................. P. pangcahae Hsueh, 2024 ( Taiwan)

21. Postero-dorsal tentacular cirri reaching chaetiger 2; mandibles with 11–12 teeth; Area VI with smooth shaped bar ................................................................................................ P. iranica Bonyadi-Nacini, Rastegar-Pouyani, Rastegar-Pouyani, Glasby & Rahimian, 2018 (Abu Musan Island, Persian Gulf)

– Postero-dorsal tentacular cirri reaching chaetiger 6; mandibles with 7 teeth; Area VI with shield-shaped bar ...................................................................... P. perspicillata ( Grube, 1878) ( Philippines)

22. Notopodial prechaetal lobe present ................................................................................................ 23 – Notopodial prechaetal lobe absent .................................................................................................. 25

23. Area III with group of 11–20 paragnaths and two lateral groups with 2–3 paragnaths in line; Area VI with one smooth straight bar in each side ................................ P. helleri ( Grube, 1878) ( Philippines) – Area III with up to 7 paragnaths, without lateral groups; Area VI with shield-shaped bar on each side .................................................................................................................................................. 24

24. Dorsum with transverse rows of unpigmented papillae; antennae ½ × as long as palpophores; ridge areas VI–V–VI with ɔc- shaped pattern ............................................................................................... P. faulwetterae Teixeira, Langeneck, Grosse, Bakken & Rava, 2025 ( Italy, Trieste, Adriatic Sea)

– Dorsum without transverse rows of papillae; antennae as long as palpophores; antennae reach anterior end of palpophore; ridge areas VI–V–VI with U-shaped pattern ....................................................... .............................. P. twobae Teixeira, Langeneck, Grosse, Bakken & Rava, 2025 ( Italy, Calafuria)

25. Ridge of areas VI–V–VI with π- shaped pattern ............................................................................. 26 – Ridge of areas VI–V–VI in another pattern .................................................................................... 27

26. Area III with group of 10–11 paragnaths and sometimes with 1–2 isolated lateral paragnaths; Area V with 3 paragnaths in triangle; Area VI with crescent-shaped bar in each side; area VII–VIII with 21–26 paragnaths inserted in forrow zone .......................................................................................... ................................................. P. misrai Prajapat, Villalobos-Guerrero & Vachhrajani, 2024 ( India) – Area III with 20–24 paragnaths in oval group; Area V with one paragnath, without lateral groups; Area V with only one paragnath; Area VI with broad petite shield-shaped bar in each side; Area VII–VIII with 30 paragnaths inserted in forrow and ridge zones ....................................................... .................................................................................... P. falsovariegata Monro, 1933 ( South Africa)

27. Neuropodial postchaetal lobe present; jaws with up to 5 teeth; Area I with 2 paragnaths in line; Area IV with up to 8–10 paragnaths; Area V with 3 paragnaths in triangle; Area VI with shield-shaped bar in each side; Area VII–VIII with 24 paragnaths in 3 regular bands; ridge of areas VI–V–VI with U-shaped pattern .................................................................. P. hourdezi sp. nov. ( Clipperton Island) – Neuropodial postchaetal lobe absent; jaws with up to 10 teeth; Area I with 3 paragnaths in triangle; Area IV with up to 18–19 paragnaths; Area V with 1 paragnath; Area VI with smooth shaped bar in each side; Area VII–VIII with 16 paragnaths in 2 regular bands; ridge of areas VI–V–VI with λ- shaped pattern ................................................................. P. websteri Conde-Vela, 2022 ( Bermuda)