Synelmis kirkegaardi, Salazar-Vallejo, 2003

Salazar-Vallejo, Sergio I., 2003, Revision of Synelmis Chamberlin, 1919 (Annelida, Polychaeta, Pilargidae), Zoosystema 25 (1), pp. 17-42 : 32-33

Synelmis kirkegaardi n. sp.

( Fig. 9 )

Synelmis albini – Kirkegaard 1983: 212, 213.

TYPE MATERIAL. — Syntypes: Atlantide Expedition, stn 43, Bahía de Praia, São Thiago Island, Cape Verde Islands, 22 m, 84 syntypes (74 complete) ( ZMUC- 905).

TYPE LOCALITY. — Bahía de Praia, São Thiago Island, Cape Verde Islands.

ETYMOLOGY. — This species is named after Dr Jorgen B. Kirkegaard, from the Zoological Museum of Copenhagen, for his many publications on polychaetes and especially for his work on the materials from the Danish Expedition to tropical West Africa, where these materials came from.

DISTRIBUTION. — Kirkegaard (1988: 75) indicated that S. albini is present in western Africa and, following Pettibone (1966), in the Indian and Pacific oceans. However, specimens from these areas have been found to belong to different species. Synelmis kirkegaardi n. sp. is restricted to sublittoral bottoms in the eastern tropical Atlantic Ocean.

DESCRIPTION

Body sub-cylindrical, tapering towards both ends, light brown or yellowish in alcohol, some specimens darker in the anterior end. Body with mid-dorsal elevation, parapodia ventrolateral expansions, and a mid-ventral deep groove, but appearance may vary according to fixation. Length 15-57 mm, width 0.4-1.0 mm, with 49-123 setigers.

Prostomium trapezoidal, with biarticulated palps separated from each other, palpostyles massive knobs with a ventral papilla on each base ( Fig. 9A ); ventral longitudinal depression on prostomium that coincides with the separation of the palps. Three similar fusiform antennae, lateral ones anteriorly placed close to the base of palps, median one placed on posterior margin of the prostomium. One pair of dark eyes located close to posterior margin of prostomium but several variations occur. Among the 84 specimens, two lacked eyes or the eyes were colorless (2.4%), three had a single eye (3.6%), eight had one eye duplicated (9.5%), each of which was smaller than the opposite eye, and in two both eyes were double (2.4%). Thus, 13 specimens had their eyes modified.

Tentacular cirri fusiform. Parapodia with similar fusiform cirri; setal lobe shorter than cirri, it can be up to half the length of either dorsal or ventral cirri. Notospines from setiger 5, exposed portion of spine up to one third the length of dorsal cirrus ( Fig. 9B ), becoming slightly more exposed in posterior setigers ( Fig. 9 C-E). Prepygidial region with thinner cirri ( Fig. 9F ). Neurosetae of three kinds: limbate setae, capillaries and two or three furcate setae with asymmetrical tines per setiger.

Pharynx short, its eversible portion can be as corresponding to two setigers, without marginal papillae though in two specimens the furrows resemble irregular papillae. Non-eversible portion of pharynx muscular, measuring 8-13 setigers in length, with multiple rows of muscular cells.

REMARKS

Synelmis kirkegaardi n. sp. resembles S. albini though it differs by having a more anterior start of notospines and by living in sublittoral bottoms.

Figures

FIG. 9. — Synelmis kirkegaardi n. sp. from Cape Verde Islands (ZMUC-905); A, anterior end in dorsal view; B, setiger 5 in posterior view; C, setiger 20 in anterior view; D, setiger 40 in anterior view; E, setiger 60 in anterior view; F, posterior end in dorsal view. Scale bars: A, F, 0.36 mm; B-E, 0.14 mm.