Harmothoe longisetis ( Grube, 1863 )

Barnich, Ruth & Fiege, Dieter, 2009, Revision of the genus Harmothoe Kinberg, 1856 (Polychaeta: Polynoidae) in the Northeast Atlantic, Zootaxa 2104 (1), pp. 1-76 : 51-54

Harmothoe longisetis ( Grube, 1863)

( Figs. 4 , 25A–I )

Polynoe longisetis Grube, 1863: 37 , pl. 4 fig.1.

Harmothoe longisetis: Fauvel (1923) : 66, fig. 24a–g [part, not Harmothoe glabra ( Malmgren, 1866) ]; Barnich & Fiege (2000): 1904 , fig. 8A–E; Barnich & Fiege (2003): 51, fig. 25A–E.

Type material. Polynoe longisetis : 2 syntypes (dry), MPW 355 , Lussin, Adriatic Sea, leg. E. Grube.

Additional material. Mediterranean: SMF 12445, St. 291, Marseille, gravelle à Peyssonnelia , 27 March 1953, Coll. Pérès.

(For further material see Barnich & Fiege 2000 and 2003).

Diagnosis. Anterior pair of eyes dorsolateral at widest part of prostomium. Elytral margin smooth; conical microtubercles in one or more patches near anterior margin. Noto- and neurochaetae with distinct rows of spines; tip of neurochaetae straight or only slightly hooked. Neuropodial supra-acicular process slender, digitiform.

Description (based on additional specimen SMF 12445, since type material in poor condition).

Body with 38 segments. At anterior end ( Fig. 25A ), prostomium bilobed, with distinct cephalic peaks; ceratophore of median antenna in anterior notch, lateral antennae inserted ventrally, styles of antennae papillate, slightly inflated subdistally, then abruptly 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 one notochaeta and a dorsal and ventral tentacular cirrus, styles of cirri papillate, slightly inflated subdistally, then abruptly 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 six segments cirrigerous; elytral margin smooth; conical microtubercles in one or more patches near anterior margin ( Fig. 25B,C ). Cirrigerous segments with distinct dorsal tubercles; dorsal cirri with cylindrical cirrophore, style papillate, slightly inflated subdistally, then abruptly tapering.

Parapodia biramous; notopodia with elongate acicular lobe; neuropodia with elongate prechaetal acicular lobe with slender, digitiform supra-acicular process; neuropodial postchaetal lobe shorter than prechaetal lobe, rounded; tips of noto- and neuroacicula penetrating epidermis ( Fig. 25D ). Notochaetae stouter than neurochaetae, with distinct rows of rather short spines and blunt to pointed tip ( Fig. 25E,F ); neurochaetae with distinct rows of spines, tips rather straight or only slightly hooked, bidentate with distinctly set off secondary tooth ( Fig. 25G–I ).

Measurements. Specimen figured, SMF 12445: L 30 mm, W 8 mm for 38 segments ( Fig. 25A–I ).

Remarks. See above in remarks sections of H. benthaliana McIntosh, 1885 and H. glabra ( Malmgren, 1866) , respectively, for distinguishing characters.

Distribution. Southern Northeast Atlantic and Mediterranean Sea.

Habitat. On hard substrates, depth unknown.

Figures

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

FIGURE 25. Harmothoe longisetis (additional specimen, SMF 12445). (A) anterior end; styles of median antenna, left tentacular cirri, and left dorsal cirrus mising; (B) right anterior elytron from unknown segment; (C) microtubercles; (D) right cirrigerous parapodium from segment 14, posterior view, style of dorsal cirrus missing; (E) long notochaeta; (F) tip of same; (G) middle neurochaeta; (H) tip of same; (I) tip of upper neurochaeta. (Scale: A, B = 2 mm; C = 100 µm; D = 1 mm; E, G = 250 µm; F, H, I = 50 µm).