Chloeia hutchingsae, Salazar-Vallejo, 2023

Salazar-Vallejo, Sergio I., 2023, Revision of Chloeia Savigny in Lamarck, 1818 (Annelida, Amphinomidae), Zootaxa 5238 (1), pp. 1-134 : 68-70

Chloeia hutchingsae sp. n.

urn:lsid:zoobank.org:act:9F7BC066-948C-45FE-959C-ADD15D972430

Fig. 30

Type material. Philippines. Holotype ( CAS 185386 ), Hearst Philippine Biodiversity Expedition 2011, M/V DABFAR, near Simo Banks (14.07° N, 120.17° E), 223–369 m, sand, 3 Jun. 2011, R. Mooi, et al., coll.

Additional material. Australia. Anterior fragment ( AM W6526 ), New South Wales, east of Malabar (33°57' S, 151°19' E), Shelf Benthic Survey, Sta. 20, 11.6 m, 18 Jan. 1973 (middorsal band expanded anteriorly, and two illdefined wide lateral bands expanded laterally beyond branchiae. Eyes blackish, anterior eyes 2× larger than posterior ones. Caruncle with 36 folds; median ridge reddish. Bipinnate branchiae with 6–7 lateral branches by chaetiger 10. Many chaetae broken; 31 mm long, 12 mm wide, 16 complete chaetigers) . Vanuatu. One specimen ( MNHN Musorstom 8-1040), RV Alis, Sta. CP 1040 (16°48.74´S, 168°30.17´E), 472– 464 m, 30 Sep. 1994, B. Richer de Forges , coll. (complete, slightly bent; notochaetae almost all lost; caruncle with middorsal ridge blackish, with 40 vertical folds; bipinnate branchiae in chaetiger 10 with 7 lateral branches; posterior end with anus terminal, anal cirri digitate, 6× longer than wide; 60 mm long, 13 mm wide, 37 chaetigers) .

Diagnosis. Chloeia with branchiae from chaetiger 4, progressively smaller posteriorly, each with 6–7 lateral branches; middorsal bands T- or Y-shaped, without lateral bands; harpoon notochaetae with short smooth tines; neurochaetae spurred and furcates.

Description. Holotype (CAS 185386), bent ventrally, some chaetae broken; body 105 mm long, 15 mm wide, 34 chaetigers.

Holotype with dorsum purplish, middorsal band expanded anteriorly in each segment, and two ill-defined wide lateral bands expanded laterally beyond branchiae, continued between parapodia ( Fig. 30A ); dorsal cirri purple, at least basally; branchial stems and bases of lateral branches purplish, branches tips pale. Venter cream, midventral band indistinct.

Prostomium anteriorly entire. Eyes blackish, anterior eyes 2–3× larger than posterior ones. Median antenna pale, inserted at anterior caruncular margin, without tip, 1/8 as long as caruncle, size proportions to lateral antennae unknown. Lateral antennae bases separate, slightly wider than palps. Mouth ventral on chaetiger 2. Pharynx barely exposed.

Caruncle grayish, sigmoid, trilobed, tapered, reaching chaetiger 4 ( Fig. 30B ). Median ridge continuous, not plicate, dark purple, with about 34 vertical folds, partially concealing lateral lobes. Lateral lobes narrow, with about 30 vertical folds.

Bipinnate branchiae from chaetiger 4, parallel throughout body, several lost (segment 16 branchiae removed), progressively larger to chaetiger 12–14, progressively smaller posteriorly. By chaetiger 15, branchiae with 6–7 lateral branches ( Fig. 30C ).

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–4, 1/3–1/4 as long as dorsal cirri. Dorsal cirri colorless along chaetigers 1–5, following segment with cirrostyle purple, cirrophores pale, slightly longer than branchiae in median segments, 2× longer in posterior chaetigers. Second ventral cirri with cirrophores 2× longer and wider, and cirrostyle 2× longer than adjacent ones, directed dorsally. Other ventral cirri directed ventrolaterally, as long as one subsequent segment.

Chaetae brittle, many broken, complete with distal hoods, rarely eroded. Notochaetae in anterior chaetigers furcates, major tines 6–12× longer than minor ones ( Fig. 30D ). Median chaetigers with two types of notochaetae: furcates with reduced minor tines, major ones 5–8× longer than minor ones, and harpoon-chaetae with denticulate tines 6–7× longer than smooth ones ( Fig. 30F ). Neurochaetae furcates and spurred, major tines 5-7× longer than minor ones, of similar proportions in anterior ( Fig. 29E ) and median chaetigers ( Fig. 30G ).

Posterior region tapered ( Fig. 30H ); anus terminal, anal cirri whitish, bent dorsally, 5–6× longer than wide.

Live pigmentation (after C. Piotrowski notes after collecting one specimen). Middorsal band purple. Caruncle blackish, median ridge grayish. Dorsal cirri dark purple basally, tips whitish. Branchiae red. Australian specimens with red pigmentation ( Fig. 30I ).

Etymology. The specific epithet is after Dr. Pat Hutchings, from the Australian Museum, Sidney, in recognition of her abundant, relevant publications in taxonomy of polychaetes and those dealing with proposals for improving funding and professional conditions of taxonomists in general. The derived name is a noun in the genitive case ( ICZN 1999, Art. 31.1.2).

Remarks. Chloeia hutchingsae sp. n. is described with specimens from The Philippines to Australia and Vanuatu; by having a complex pigmentation pattern, and bipinnate branchiae from chaetiger 4, progressively smaller posteriorly, it belongs in the group viridis. Because of the presence of a well-defined middorsal band, without lateral bands, C. hutchingsae resembles C. zibrowi sp. n. described below from the French Polynesia; they are also similar after the size of eyes and the type of chaetae. However, these two species differ especially in the pigmentation of caruncle, its vertical folds, and in the number of branchial lateral branches in median segments. In C. hutchingsae caruncle is pale, with blackish median ridge, with 34 vertical folds, and its branchiae are delicate, each with 11–12 lateral branches, whereas in C. zibrowii caruncle is blackish, with 24 vertical folds, and its branchiae are massive, with 6–7 lateral branches.

Distribution. The Philippines to Australia and Vanuatu, in sediments at 12–472 m water depth; however, the shallow water anterior fragment (AM W6526) differs and it is herein included with hesitation Better preserved specimens would help clarify its affinities.

Figures

FIGURE 29. Chloeia gilleti sp. n., holotype (MMSUCO Amp 7). A. Anterior region, dorsal view. B. Anterior end, dorsal view. C. Chaetigers 14-16, dorsal view (branchiae removed from chaetiger 15). D. Chaetiger 3, notochaetal tips. E. Same, neurochaetal tips. F. Chaetiger 17, harpoon notochaetae. G. Same, neurochaetal tips. H. Posterior region, dorsal view. Scale bars:A, H, 1 mm; B, 0.6 mm; C, 0.7 mm; D, F, 100 μm; E, G, 40 μm.

FIGURE 30. Chloeia hutchingsae sp. n. A. Holotype (CAS 185386), anterior region, dorsal view. B. Anterior end, dorsal view. C. Chaetigers 15-17, dorsal view (branchiae removed from chaetiger 16). D. Chaetiger 4, notochaetal tips. E. Same, neurochaetal tips. F. Chaetiger 11, harpoon notochaetal tips. G. Chaetiger 10, neurochaetal tips. H. Posterior region, dorsal view. I. Non-type specimen (AM W6526), anterior region, dorsal view. Scale bars: A, C, H, 2 mm; B, 1 mm; D, 130 μm; E, 50 μm; F, 180 μm; G, 120 μm; I, 3 mm.