Harmothoe mariannae, Barnich & Fiege, 2009

Barnich, Ruth & Fiege, Dieter, 2009, Revision of the genus Harmothoe Kinberg, 1856 (Polychaeta: Polynoidae) in the Northeast Atlantic, Zootaxa 2104 (1), pp. 1-76 : 54-56

Harmothoe mariannae n. sp.

( Figs. 3 ; 26A–J )

Type material. H. mariannae n. sp.: holotype (cs in three fragments), SMF 17290, "Johan Ruud" St. 482, 69°52.36’N 30°08.09’E, N Norway, Varangerfjord , Bøkfjord Kjelmsøy lykt, 10 May 2006, epibenthic sledge, 251 m, leg. & ded. C. d’Udekem d’Acoz .

Paratype (cs in two fragments), SMF 17293, Vigdis 1999, St. 17-1, 30 May 1999, 61°22'52.84'' N, 02°06'37.19'' E, 280 m, ded. A. Sikorski .

Diagnosis. Anterior pair of eyes dorsolateral at widest part of prostomium. Elytral margin and adjacent surface papillate, papillae long at outer lateral margin, becoming shorter towards posterior margin; surface with conical microtubercles; macrotubercles conical to low, globose, scattered in a row near posterior margin.

Description (based on holotype).

Body with 36 segments. At anterior end ( Fig. 26A ), 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 papillate, tapering.

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, slightly papillate 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 four segments cirrigerous; elytral margin and adjacent surface papillate, papillae long at outer lateral margin, becoming shorter towards posterior margin; surface with conical microtubercles; macrotubercles conical to low, globose, scattered in a row near posterior margin. ( Fig. 26B,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 long, digitiform supra-acicular process; neuropodial postchaetal lobe shorter than prechaetal lobe, rounded; tips of noto- and neuroacicula penetrating epidermis ( Fig. 26D ). Notochaetae stouter than neurochaetae, with distinct rows of spines and blunt tip ( Fig. 26E,F ); neurochaetae with distinct rows of spines, upper group bidentate with short, stout secondary tooth, lower group unidentate ( Fig. 26G–J ).

Measurements. Holotype (cs), SMF 17290 ( Fig. 26A–J ): L 16 mm, W 4 mm for 36 segments. Paratype, SMF 17293 (cs): L 13 mm, W 4 mm for 33 segments.

Remarks. Harmothoe mariannae n. sp. is similar to H. vesiculosa Ditlevsen, 1917 , but in this species elytra show shorter marginal papillae and macrotubercles are smaller and arranged in a dense row near the posterior margin. Confusion might also be possible with H. multisetosa Moore, 1902 from the Northeast Pacific. Here elytra have shorter marginal papillae, macrotubercles are not only present near the posterior margin, but also scattered on the surface, and microtubercles are conical to pointed (cf. Moore 1902 and Pettibone 1953).

Distribution. Northeast Atlantic, from northern Norway to the northern North Sea.

Habitat. Unknown, in 251 to 280 m.

Etymology. The species is named after Marianne Barnich-Brimaire for her continuous support and interest in our work.

Figures

FIGURE 3. Identification characters of Harmothoe impar, H. clavigera, H. rarispina, H. extenuata, H. fragilis, H. vesiculosa, H. abyssicola, and H. mariannae n. sp.

FIGURE 26. Harmothoe mariannae n. sp. (holotype, SMF 17290). (A) anterior end; (B) second right elytron from segment 4; (C) detail of posterior margin of same; (D) left cirrigerous parapodium from segment 14, posterior view, style of dorsal cirrus not figured; (E) distal part of long notochaeta; (F) tip of same; (G) distal part of middle neurochaeta; (H) tip of same; (I) tip of upper neurochaeta; (J) tip of lower neurochaeta. (Scales: A, B = 1 mm; C = 250 µm; D = 500 µm; E, G = 100 µm; F, H–J = 50 µm).