Chloeia poupini, Salazar-Vallejo, 2023

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 95-96

Chloeia poupini sp. n.

urn:lsid:zoobank.org:act:015CE52A-FE25-4746-A636-DA995B8D77A6

Fig. 44

Type material. French Polynesia. Holotype ( MNHN IA-TYPE 2053), RV Marara, Sta. unnumb., South of Fangatufa (22°18´S, 138°46´W), 860 m, deep-sea trap, 23 Nov. 1988, J. Poupin, coll.

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 4, progressively smaller posteriorly; anterior prostomial area blackish; middorsal band wide, medially separated along a few anterior chaetigers; notochaetae furcates and harpoon chaetae with basal tines; neurochaetae furcates.

Description. Holotype (MNHN IA-TYPE 2053) complete, depressed; body fusiform ( Fig. 44A ), 47 mm long, 12 mm wide, 28 chaetigers.

Holotype pale, chaetae whitish, traslucent; a wide reddish middorsal band along chaetigers 4–9; branchiae and dorsal cirri pale. Venter pale, midventral whitish band along body.

Prostomium anteriorly entire; anterior prostomial area blackish, separated into two lateral lobes ( Fig. 44B ). Eyes indistinct. Median antenna inserted at anterior caruncular margin, without tip, slightly shorter than caruncle, 2× longer than lateral antennae. Lateral antennae bases separated, slightly longer than palps. Mouth ventral on chaetiger 2. Pharynx not exposed.

Caruncle darker than adjacent body wall, contracted, bent laterally, reaching chaetiger 4. Median ridge distorted by compression, with about 30 vertical folds, partially covering lateral lobes. Lateral lobes wide, with about 30 vertical folds.

Bipinnate branchiae from chaetiger 4, contracted, continued throughout body, parallel along most body segments; progressively larger to chaetiger 7–12, progressively smaller posteriorly. Median segments with 7–8 lateral branches, each with a few secondary filaments.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–3, slightly and progressively short-er than dorsal cirri. Dorsal cirri about 2× longer than bipinnate branchiae along median chaetigers, 3× longer in posterior chaetigers. Second ventral cirri with cirrophores 2× longer and 3× wider, and cirrostyles 2× longer than adjacent ones, directed dorsally. Other ventral cirri directed ventrolaterally, as long as 2–3 subsequent segments.

Chaetae mostly complete. Complete chaetae with distal fragile hoods, most intact. Anterior notochaetae furcates ( Fig. 44C ), major tines 3–4× longer than minor ones. Median notochaetae mostly smooth furcates and harpoon furcates ( Fig. 44E ), major tines 2–3× longer than minor ones. Neurochaetae all furcates, major tines 3–4× longer than minor ones in anterior chaetigers ( Fig. 44D ), 6–11× longer in median chaetigers ( Fig. 44F ).

Posterior region tapered ( Fig. 44G ); pygidium with anus terminal; anal cirri pale, digitate, 4× longer than wide.

Live pigmentation. Unknown; probably more intense pigmentation than currently observed in holotype. Middorsal reddish band along chaetigers 4–9; dorsal cirri and branchiae pale. Caruncle darker than body wall.

Etymology. This species is named after Dr. Joseph Poupin, a French carcinologist who worked for the Service Mixte de Surveillance Radiologique et Biologique, who was responsible for a long-term sampling effort in the French Polynesia, including deep sea traps (Popuin 1991, 1996); in one of them he found the holotype for this new species. The derived name is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Remarks. Chloeia poupini sp. n. is described with a single specimen from the French Polynesia trapped in deep water sediments. By having a middorsal regular band, continuous along each segment, and bipinnate branchiae from chaetiger 4, progressively smaller posteriorly, it belongs in the group venusta. Further, because it has furcates in anterior chaetigers, and harpoon notochaetae in median chaetigers, it resembles C. venusta de Quatrefages, 1866 , from the Mediterranean Sea, redescribed below. The main differences between these two species are in the pigmentation of the anterior prostomial area, and type of furcate neurochaetae. Thus, C. poupini has a blackish anterior prostomial area, and its neurochaetae have major tines 5–6× longer than minor ones, whereas in C. venusta the anterior prostomial area is pale, and its neurochaetae have major tines 2× longer than minor ones.

Distribution. French Polynesia, in sediments at 860 m water depth.

Figures

FIGURE 44. Chloeia poupini sp. n., holotype (MNHN IA-TYPE 2053). A. Dorsal view. B. Anterior region, dorsal view. C. Chaetiger 4, notochaetal tips. D. Same, neurochaetal tips. E. Chaetiger 15, notochaetal tips (inset: denticulate portion). F. Same, neurochaetal tips. G. Posterior end, dorsal view. Scale bars: A, 4.4 mm; B, 1.8 mm; C, 240 μm; D, F, 150 μm; E, 260 μm; G, 1 mm.