Chloeia fauveli, Salazar-Vallejo, 2023

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 43-44

Chloeia fauveli sp. n.

urn:lsid:zoobank.org:act:CCCE704E-661C-420B-9EE3-D2DC5FFAD2E2

Fig. 17

Chloeia rosea: Fauvel 1932: 57 ; Fauvel 1953: 97–98, Fig. 46h (partim, RV Investigator, Sta. 242 is C. tumida Baird, 1868 ; non Potts, 1909).

Type material. Bay of Bengal. Holotype ( MNHN IA-TYPE 2049 ), and paratype ( MNHN IA-TYPE 2051 ), RIMS Investigator , Sta. XX (no coordinates available; see Anonymous 1914 in Huys et al. 2014), 117 m, 1885 (paratype data in variation).

Diagnosis. Chloeia with bipinnate massive branchiae from chaetiger 4, stems basally purplish, progressively smaller posteriorly; dorsum pale; anterior chaetigers with harpoon notochaetae, without spurs; neurochaetae spurred and furcates.

Description. Holotype (MNHN IA-TYPE 2049), complete, slightly bent ventrally, body 29 mm long, 9 mm wide, 28 chaetigers.

Holotype pale; dorsum without pigmentation pattern ( Fig. 17A ); dorsal cirri purplish; branchiae pale, pink in posterior region; anterior prostomial area grayish; chaetae transparent to yellowish. Venter cream, midventral band wide, paler.

Prostomium anteriorly entire, anterior region grayish. Eyes black, anterior eyes 8–10× larger than posterior ones ( Fig. 17B, C ). Median antenna complete, pale, inserted at anterior caruncular margin, 1/3 as long as caruncle, slightly longer than lateral antennae. Lateral antennae bases separated from each other, slightly longer than palps. Mouth ventral on chaetiger 2. Pharynx not exposed.

Caruncle pale, sigmoid, trilobed, tapered, reaching chaetiger 5. Median ridge plicate, pale, with about 30 vertical folds, almost completely concealing lateral lobes. Lateral lobes narrow, with about 30 vertical folds.

Bipinnate branchiae from chaetiger 4, parallel or slightly divergent along body, progressively larger to chaetiger 13–14, smaller posteriorly; in median segments branchiae with 12–13 lateral branches ( Fig. 17D ).

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–3, progressively shorter, ½–1/3 as long as dorsal cirri. Dorsal cirri slightly longer than bipinnate branchiae along median chaetigers, 2× longer in posterior chaetigers. Second ventral cirri with cirrophores 3× longer and wider, and cirrostyle 2–3× longer than adjacent ones, directed dorsally. Other ventral cirri directed ventrolaterally, slightly longer than one subsequent segment.

Chaetae most complete with hoods, rarely eroded. Notochaetae in anterior chaetigers include a few furcates, major tines 4–6× longer than minor ones, and harpoon-chaetae, with or without smooth tines ( Fig. 17E ). Median chaetigers with one type of notochaetae: harpoon-chaetae without tines ( Fig. 17G ). Neurochaetae furcates and spurred, major tines 5–12× longer than minor ones, a few with spurs (major tines over 10× longer than minor ones) along anterior ( Fig. 17F ) and median chaetigers ( Fig. 17H ).

Posterior region tapered ( Fig. 17I ); pygidium with anus terminal; anal cirri lost.

Live pigmentation. Unknown. Its pink body was probably used for identifying it as C. rosea ; likely more intense in living specimens.

Etymology. The species name is after the late Dr. Pierre Fauvel in recognition of his many publications on polychaetes, and especially because he studied the type specimens included in the above description. The derived name is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Variation. Paratype ( MNHN IA-TYPE 2051) complete, bent ventrally, body 27 mm long, 9 mm wide, 27 chaetigers; dorsal cirri and ventral cirri of chaetiger 2 purplish; branchial stems purplish; anterior eyes 5–6× larger than posterior ones. Median antenna with ceratostyle broken. Branchiae large, massive, completely covering dorsum along median and posterior chaetigers. Anal cirri lost .

Remarks. Chloeia fauveli sp. n. is described after some specimens collected in the Bay of Bengal. It belongs in the group tumida because it lacks a dorsal pigmentation pattern, and has bipinnate branchiae from chaetiger 4, progressively smaller posteriorly. Further, by having caruncle tapered and pigmented dorsal cirri and branchiae, C. fauveli resembles C. murrayae sp. n. from Australia. The main differences between these two species are in the size of anterior and posterior eyes, development of bipinnate branchiae, and type of notochaetae in anterior chaetigers. Thus, C. fauveli has anterior eyes 8–10× larger than posterior ones, branchiae massive, and harpoon notochaetae in chaetiger 3, whereas in C. murrayae anterior eyes 3–4× larger than posterior ones, branchiae are delicate, and there are no harpoon notochaetae in anterior chaetigers.

Fauvel (1932) identified as C. rosea Potts, 1909 the type specimens. However, C. rosea is unique by having branchiae pinnate, not bipinnate, starting from chaetiger 5, and it was found on a purple alcyonarian in substrates at 54 m water depth. These specimens have massive bipinnate branchiae from chaetiger 4, and were dredged from sediments at 117 m water depth. The handwritten label by Fauvel has a question mark for the species name. He also indicated the species was abundant and followed Potts who had noted that “It is very noticeable how closely this species adheres to the C. fusca type. The only differences from the original species are but trifling, viz., the coloration, structure, and arrangement of gills and the absence of a single type of chaetae” ( Potts 1909; 358) Fauvel concluded by indicating “it is probably a young form of C. fusca , or a colour variety” ( Fauvel 1932:57, 1953: 97). These conclusions and perspectives cannot be sustained and consequently, C. fauveli is different from C. rosea .

Distribution. Bay of Bengal, in sediments at 117 m water depth.

Figures

FIGURE 17. Chloeia fauveli sp. n., holotype (MNHN IA-TYPE 2049).A.Anterior region, dorsal view. B. Anterior end, dorsal view, after Methyl green staining. C. Same, right lateral view. C. Chaetigers 12-15, dorsal view, after Methyl Green staining. E. Chaetiger 3, furcate and harpoon notochaetae (inset: tip of harpoon chaetae). F. Same, tips of neurochaetae. G. Chaetiger 14, harpoon notochaetae (inset: tip of harpoon chaetae). H. Same, tips of neurochaetae. Scale bars: A, 2.2 mm; B, 0.7 mm; C. 0.9 mm; D, 1.8 mm; E, 250 μm; F, H, 80 μm; G, 300 μm; I, 2.o mm.

FIGURE 46. Chloeia pulchella Baird, 1868, reinstated.A. Holotype of C. p. pallida Baird, 1868 (BMNH 1846.10.14.60), anterior end, dorsal view, after Methyl green staining. B. Chaetigers 17-20, dorsal view. C. Posterior region, dorsal view. D. Syntype of C. incerta de Quatrefages, 1866 (MNMH IA-TYPE 248), beheaded, anterior end, dorsal view. E. Chaetigers 16-19, dorsal view. F. Posterior region, dorsal view. Scale bars: A, E, 0.9 mm; B, 1.1 mm; C, 1.5 mm; D, 1.4 mm; F, 1.9 mm.