Terebellides sp. 5

Schüller, M. & Hutchings, P. A., 2012, New species of Terebellides (Polychaeta: Trichobranchidae) indicate long-distance dispersal between western South Atlantic deep-sea basins, Zootaxa 3254, pp. 1-31 : 27

Terebellides sp. 5 SA

Figs 19–20

Material examined: Diva 3; st 534; EBS; 36°0.61'S, 49°1.54'W, 4a607.8 m (start trawl) to 36°0.70'S, 49°1.73'W, 4576.1 m (gear off ground); 16.07.2009; Argentine Basin (1 specimen, ZMH-25954)

Description: Specimen 6 mm long, 2 mm wide, incomplete.

Prostomium with lower lip slightly expanded ( Figs 19, 20a). Tentacular membrane somewhat stout and fleshy, with buccal tentacles of short length and simple tips, possibly representing the bases of longer tentacles ( Figs 19, 20b). Upper lip slightly visible, mostly covered by lower lip. First and second segment hardly visible in lateral view. Lateral lappets on segments 3–8 (TC-1 - 6), well developed, size usually TC-1> TC-2 <TC-3> TC-4> TC- 5> TC-6 ( Figs 19, 20a).

Ventral glandular bands and glandular areas around parapodia absent. Nephridial papillae inserted dorsally to notopodia of segments 3, 6, and 7.

Branchiae consisting of a stout single stem dorsally between TC-1 and TC-2. Four branchial lobes completely free from each other, bearing broad, diamond-shaped lamellae that are loosely packed. Posterior lobes shorter (about 80%) and less in diameter than anterior lobes. Branchial stem annulated, filamentous tips at end of branchial lobes absent.

Notopodia all comparably well developed throughout thorax, that of TC-1 smaller than subsequent. Notochaetae all simple capillaries.

First neuropodia from segment 8 (TC-6), with neuropodia as sessile pinnules in thorax. First neuropodium (TC-6) bearing acicular hooks, visible even under low light-magnification. Subsequent thoracic neuropodia with a series of long-handled uncini. Abdominal neuropodia and pygidium unknown.

MG staining ( Figs 20a, b) corresponds with staining pattern 7 ( Schüller & Hutchings 2010), with all TCs striped. Clearly apparent white bands missing. Notopodia unstained while neuropodia bear a green colouration with fresh staining.