Harmothoe evei Kirkegaard, 1980

Barnich, Ruth & Fiege, Dieter, 2009, Revision of the genus Harmothoe Kinberg, 1856 (Polychaeta: Polynoidae) in the Northeast Atlantic, Zootaxa 2104 (1), pp. 1-76 : 30-31

Harmothoe evei Kirkegaard, 1980

( Figs. 4 ; 14A–H )

Harmothoe evei Kirkegaard, 1980: 82 fig. 1a–d.

Type material. Harmothoe evei : holotype, BMNH ZB 1983.1767 , RRS "Shackleton" St. 1903/7, off Brittany, 47°29.94'N 9°33.40'W, April 1977, SMBA sledge, 4250 m .

Diagnosis. Anterior pair of eyes dorsolateral at widest part of prostomium. Elytral margin and adjacent surface with scattered, short papillae; surface covered by spine-shaped microtubercles.

Description (based on holotype).

Body with 35 segments. At anterior end ( Fig. 14A ), prostomium bilobed, with distinct cephalic peaks; ceratophore of median antenna in anterior notch, lateral antennae inserted ventrally, styles of antennae papillate, tapering; anterior pair of eyes situated dorsolaterally at widest part of prostomium, posterior pair dorsally near hind margin of prostomium; palps missing.

Tentaculophores inserted laterally to prostomium, each with two notochaetae and a dorsal and ventral tentacular cirrus, styles of cirri papillate, tapering. Second segment with first pair of elytra, biramous parapodia, and long buccal cirri. Following segments with tapering, short ventral cirri.

Fifteen pairs of elytra, covering dorsum, on segments 2, 4, 5, 7, then on every second segment to 23, 26, 29, 32; last three segments cirrigerous; elytral margin and adjacent surface with scattered, short papillae; surface covered by spine-shaped microtubercles ( Fig. 14B, C ). Cirrigerous segments with distinct dorsal tubercles; dorsal cirri with cylindrical cirrophore, style papillate, tapering.

Parapodia biramous; notopodia with elongate acicular lobe; neuropodia with elongate prechaetal acicular lobe with digitiform supra-acicular process; neuropodial postchaetal lobe shorter than prechaetal lobe, rounded; tips of noto- and neuroacicula penetrating epidermis ( Fig. 14D ). Notochaetae stouter than neurochaetae; with distinct rows of spines and blunt tip ( Fig. 14E ); neurochaetae with distinct rows of spines, upper bidentate with slender secondary tooth, middle and lower unidentate, with rather long, straight bare part ( Fig 14F–H ).

Measurements. Holotype of H. evei ( Fig. 14A–H ): L 18 mm, W 5 mm for 35 segments.

Remarks. Harmothoe evei may be confused with H. bellani Barnich & Fiege, 2000 from shallow depths in the Mediterranean. Harmothoe bellani has elytra with long marginal papillae and the neurochaetae have a typically bent, falcate tip, while in H. evei marginal papillae are scattered and short and the neurochaetal tip is rather straight.

Distribution. Only known from the type locality in the Northeast Atlantic, off Britany.

Habitat. Abyssal depths, in 4250 m.

Figures

FIGURE 4. Identification characters of Harmothoe pokoui, H. bellani, H. evei, H. benthaliana, and H. longisetis.

FIGURE 14. Harmothoe evei (holotype, BMNH ZB 1983.1767). (A) anterior end; palps and styles of median antenna, left tentacular cirrus, and left dorsal cirrus missing; (B) left middle or posterior elytron from unknown segment, free in vial; (C) detail of lateral margin of same; (D) right elytragerous parapodium from segment 13, posterior view, style of dorsal cirrus missing; (E) distal part of long notochaeta; (F) tip of upper neurochaeta; (G) tip of middle neurochaeta; (H) tip of lower neurochaeta. (Scales: A = 2 mm; B, D = 1 mm; C = 250 µm; E = 100 µm, F–H = 50 µm).