Terebellides

Schüller, Myriam & Hutchings, Pat, 2013, New species of Terebellides (Polychaeta: Trichobranchidae) from the deep Southern Ocean, with a key to all described species, Zootaxa 3619, pp. 1-45 : 30

Terebellides sp. B

Figs 23 , 24

Material examined: DZMB-HH 6071, ANDEEP I, St. 46-5, GKG (ZMH-26013)

Description:

Single specimen 5 mm in length, 5 mm in width, complete with 18 thoracic chaetigers and 22 abdominal uncinigers.

Head region: Tentacular membrane compact, but expanded and folded. Lower lip rectangular, distinctly smaller compared to tentacular membrane. Tentacles short simple ones on outer margins of tentacular membrane and longer ones with expanded tips present ( Fig. 23 ).

Branchiae: Branchial lobes lost. Annulation of branchial stem not determinable.

Anterior chaetigers: First notopodial chaetiger reduced in size with chaetae more or less originating from body wall.

Geniculate hooks: Present on TC-6 (segment 8) only, sharply bent.

Lateral lappets: Present from TC-1–6 or -7, with TC-1=2=3>4<5=6(=7?).

Ventral pads: Chaetigers 1–5 forming distinct ventral glandular collars with anterior margins elevated, wider than following chaetigers which are not as glandular and with compact anterior margins. Nephridial papillae: Segments 3, 6, 7.

MG staining pattern 1 ( Figs 2 , 24 ): more or less striped throughout, no staining from TC-13. Anterior margins of TC-1 and -2 darker than subsequent, white bands absent ( Fig. 24 B). Noto- and neuropodia stain.

Pygidium: 2 low and blunt lateral papillae.

Remarks: The species differs from all other species described from the region by having a stout lower lip which is short and rectangular and very inconspicuous compared to other known species of Terebellides .

Habitat: Drake Passage, in 2894 m.

Figures

FIGURE 2. MG staining patterns of observed species, adapted and extended from Schüller & Hutchings (2010).

FIGURE 23. Terebellides sp. B (ZMH- 26013), A—anterior thorax, ventral, B—schematic outline of anterior thorax, lateral.

FIGURE 24. Terebellides sp. B (ZMH- 26013), MG-staining, A—anterior thorax, dorsal, B – anterior thorax, ventral.