Eunice Berthold, 1827
Eunice cf. pennata (Müller, 1776)
Voucher specimen. LOLIGO: station 1MFA; INFLEXIBLE: station 2MFB and 5MFA.
Diagnosis. Even the largest voucher (LOLIGO 1MFA) is a small, fragile, but complete specimen with 38 chaetigers, 7mm long and 0.8mm wide (including parapodia).
Prostomium with 5 articulated antenna, with the median antenna longest, the shortest ventralmost pair bi-articulated; with a pair of very small red eyes located postero-laterally on prostomium. Peristomium broad, with a pair of short tentacular cirri. Branchiae present from chaetiger 3 to chaetiger 16 branched (with single filaments from chaetiger 3 to chaetiger 8; maximally with 2 filaments), distinctly longer than notopodial cirri in anterior and middle branchial chaetigers, with single short filament in posterior most branchial chaetigers. Ring-shaped bases in posterior notopodia not confirmed. Chaetae including smooth limbate chaetae and compound bidentate falcigers present in all chaetigers, additionally bidentate subacicular hooks, appearing singly from chaetiger 11; pectinate chaetae not clearly observed. Pygidium with two long lateral and one very short dorsomedial anal cirri, all slender, without articulations. Maxillary formula not examined (specimen small and fragile).
Remarks. Small size and underdeveloped branchiae suggest these specimens may be juveniles (see also Orensanz, 1990). Eunice pennata is a cosmopolitan species with wide distribution, including previous report from the region (see Orensanz, 1990 and more recently Quiroga and Levin, 2010 for detailed discussion). Fauchald (1992) mentioned that besides branchiae starting on chaetiger 3, the unique feature of the species is the presence of ring-shaped bases in posterior notopodia (see also Quiroga and Levin, 2010), which was not confirmed in Falkland Islands specimens, likely due to their small size. Given that type locality of Eunice pennata is Norway (Oslofjord), we prefer to assign Falkland Islands’ specimens to Eunice cf. penata until molecular evidence becomes available.
REFERENCES
Fauchald, K. 1992. A review of the genus Eunice (Polychaeta: Eunicidae) based upon type material. Smithsonian Contribution. Zoology 523: 1-422.
Orensanz, J.M. 1990. The eunicemorph Polychaete annelids from Antarctic and Subantarctic seas. With addenda to the Eunicemorpha of Argentina, Chile, New Zealand, Australia, and the Southern Indian Ocean. Biology of the Antarctic Seas XXI. Antarctic Research Series 52: 1-183.
Quiroga, E. and Levin, L.A., 2010. Eunice pennata (Polychaeta: Eunicidae) from active and passive cold seep sites in Central and Southern Chile (36 °-46 ° S). Anales del Instituto de la Patagonia 38, No. 2, pp. 31-37).
