Ophelina robusta , Schüller, Myriam, 2008

Schüller, Myriam, 2008, New polychaete species collected during the expeditions ANDEEP I, II, and III to the deep Atlantic sector of the Southern Ocean in the austral summers 2002 and 2005 — Ampharetidae, Opheliidae,, Zootaxa 1705, pp. 51-68: 60-62

publication ID

10.5281/zenodo.180892

persistent identifier

http://treatment.plazi.org/id/03DB87D6-3B5B-E717-FF7D-F8BF30C2E4C8

treatment provided by

Plazi

scientific name

Ophelina robusta
status

sp. nov.

Ophelina robusta  sp. nov.

( Fig. 4View FIGURE 4. A – B C–D)

Holotype. ANDEEP I – II; Weddell Sea, Antarctic Peninsula, Sta. 131 - 3, 0 5 March 2002, 65° 19.83 ’S, 51 ° 31.62 ’W, 3049–3050 m, EBS, ZMHAbout ZMH P- 24759.

Paratype. ANDEEP III, Weddell Sea, Sta. 121 -11, 14 March 2005, 63° 38.27 'S, 50 ° 37.16 'W, 2668 m, EBS, 4 specimens, ZMHAbout ZMH P- 24760.

Additional material. 78 - 9 (10), 80 - 9 (2), 150 - 6 (5), 151 - 7 (2), 153 - 7 (7).

Etymology. The name refers to the presence of a very robust ventral cirrus on the anal tube.

Diagnosis. A diagnostic character of this species is the presence of median sized branchiae in the first 7– 8 parapodia. Enlarged branchiae are present in the posterior region of the body. The anal tube bears a robust ventral cirrus.

Description. Holotype complete, 18 mm long and 1.5 mm wide for 30 chaetigers.

A species of median size. Length about 18–23 mm, width 1–2 mm, number of chaetigers between 30–35. Color in alcohol a light tan.

Prostomium conical, carrying a distinct palpode. Peristomium limited to the lips. Nuchal organs present, but indistinct. Eyes absent ( Fig. 4View FIGURE 4. A – B C).

First follwing segment achaetous. Subsequent segments with reduced button-shaped parapodia. Anterior chaetigers with slight annulation. Segmental sutures indistinct in median body region becoming more apparent in posterior body region.

Chaetae simple capillaries throughout, anterior ones long and curved, median ones short, and posterior ones longer but few.

Anterior 7–8 branchiae distinct, of median length. Very small and indistinct branchiae in median body region becoming long and flat in posterior part of body.

Posterior chaetigers laterally flattened, terminally with an anal tube. Anal tube pseudoarticulated, bearing a robust ventral cirrus ( Fig. 4View FIGURE 4. A – B D).

Remarks. The species is similar to Ophelina setigera  and O. ammotrypanella  sharing the presence of prolonged chaetae in anterior segments. It differs from both species by bearing a robust ventral cirrus on the anal tube. The anterior branchiae are larger than that of O. ammotrypanella  , but still shorter than the posterior branchiae of both species.

Distribution. Atlantic sector of Southern Ocean and Antarctic Peninsula, 1178–3138 m

ZMH

Zoologisches Museum Hamburg