Chloeia fiegei sp. n.

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Fig. 18

Type material. Red Sea. Holotype (SMF 3814), Central Basin, MeSedA-II, RV Valdivia, Sta.Va22/111TA (21°28.97´N, 38°15.55´E, after Ţrkay 1986: 150), ST-235, 740– 785 m, 12 Apr. 1979, H. Thiel & M. Ţrkay, coll.

Diagnosis. Chloeia with bipinnate branchiae from chaetiger 4, lateral branches tapered; dorsum pale; anterior prostomial area blackish; notochaetae acicular and harpoon-chaetae without spurs; neurochaetae spurred to furcates.

Description.

Holotype (SMF 3814), damaged, many notochaetae broken, soft; posterior end eroded, almost without chaetae; body tapered, 22 mm long, 5 mm wide, 28 chaetigers (Fig. 18A).

Holotype colorless, whitish (Fig. 18A), anterior prostomial area and upper lip area dark purple, with a few darker spots (Fig. 17C). Dorsal cirri and branchiae colorless (Fig. 18B). Chaetae transparent. Venter pale, midventral band wide, visible along body.

Prostomium anteriorly entire. Eyes not seen. Median antenna inserted at anterior caruncular margin, ceratostyle lost; size relationships to lateral antennae unknown. Lateral antennae bases separate from each other, slightly longer than palps. Mouth ventral on chaetiger 2. Pharynx not exposed.

Caruncle pale, sigmoid, trilobed, tapered, reaching chaetiger 3. Median ridge plicate, colorless, with about 15 vertical folds, almost completely concealing lateral lobes. Lateral lobes narrow, with about 18 vertical folds.

Bipinnate branchiae from chaetiger 4, parallel throughout body, progressively larger to chaetiger 11–12, smaller posteriorly. Median segments with 8–9 lateral branches.

Parapodia biramous, notopodia with cirriform branchiae along chaetigers 1–3, progressively smaller than dorsal cirri. Dorsal cirri as long as bipinnate branchiae along median chaetigers, slightly longer in posterior chaetigers (most cirri lost in posterior region). Second ventral cirri with cirrophores 2× longer and wider, and cirrostyle 3× longer than adjacent ones, directed dorsally. Other ventral cirri directed ventrolaterally, as long as two subsequent segments.

Chaetae most broken, especially notochaetae. Chaetae often with distal hoods, rarely eroded. Notochaetae in anterior chaetigers furcate, major tines 3–4× longer than minor ones (Fig. 18D). Median chaetigers with two types of furcate notochaetae: furcates with major tines 3–4× longer than minor ones, and harpoon-chaetae with short smooth tines, 1/5–1/4 as long as denticulate ones (Fig. 18F). Neurochaetae spurred and furcates, major tines 12–25× longer than minor ones (Fig. 18E), 5—30× longer in median chaetigers (Fig. 18G).

Posterior region subcylindrical; pygidium with anus terminal; anal cirri lost (Fig. 18H).

Live pigmentation. Unknown.

Etymology. The specific epithet is derived after Dr. Dieter Fiege, taxonomist and curator of polychaetes in the Senckenberg Museum in Frankfurt, Germany, in recognition of his many publications on polychaetes, and of his kind support to my research activities. The derived name is a noun in the genitive case (ICZN 1999, Art. 31.1.2).

Remarks. Chloeia fiegei sp. n. is being described with specimens from a single locality in the Red Sea; it belongs in the group tumida by having bipinnate branchiae from chaetiger 4, progressively smaller posteriorly, and without dorsal pigmentation pattern. It resembles C. gesae sp. n., also described from deep water sediments along the Northeastern Atlantic, because both species have body fusiform, and bipinnate branchiae with 8–9 lateral branches. These two species differ in the pigmentation of the anterior prostomial area and dorsum, the branchial branches tips, and type of harpoon notochaetae. In C. fiegei, the anterior prostomial area is blackish, the body wall is whitish, branchial branches are tapered, and harpoon chaetae have short smooth tines, whereas in C. gesae, the anterior prostomial area is pale, the body wall is pinkish, the branchial branches are blunt, and harpoon chaetae lack tines.

Distribution. Red Sea, in sediments at 740–745 m water depth.