Syllinae Rioja, 1925
Syllis Savigny in Lamarck, 1818
Syllis sclerolaema Ehlers, 1901
Vouchers. VINSON WEST: station 1MFA; ENDEAVOUR: station E4FB (2 specimens).
Diagnosis. All vouchers posteriorly incomplete; medium sized species; body robust, dorsoventrally flattened, 2-4mm long, 0.5-0.8mm wide for anterior fragments with 18 and 27 chaetigers. Integument smooth; colour in alcohol pale pink to dark yellow; proboscis not everted.
Prostomium much wider than long bearing three antennae and two palps. Palps distinctly longer than prostomium, wide rounded lobes, basally free from each other; distally often folded over. Antennae long, thin, distinctly articulated, positioned anteriorly to eyes; lateral antennae slightly shorter (with around 25 articulations) than median antenna (with around 35 articulations). Eyes present, 2 pairs, brown-reddish, faint, positioned next to each other in almost horizontal line, with outer pair large cup-shaped, inner pair, small, spherical. Pharyngeal tube extending through 10 chaetigers, proventricle with small muscle rings extending through chaetigers 11-25. First segment achaetous laterally with a pair of long, slender, distinctly articulated tentacular cirri (similar to antenna).
Parapodia uniramous; with long, slender, distinctly articulated dorsal cirri (similar to tentacular cirri and antennae) of alternating lengths, longer ones with about 45 and shorter ones with about 20 articulations; ventral cirri only weakly articulated, slender, long (just surpassing the paprapodia), inserted basally.
Chaetae all compound falcigers, about 6 per fascicle; all with very short, thick, smooth, bidentate blades. Pygidium not observed.
Remarks. Ehlers (1901) described S. sclerolaema from Strait of Magellan. Monro (1930) reported this species from Falklands based on 2 damaged specimens, however his illustration of chaetae fits those of specimen collected here well - only falcigers, with few extremely short, thick smooth, distinctly bidentate hooks. However, it is not clear if Ehler's and Monro's specimens represent the same species. Some authors, consider S. scerolaema junior synonym of Haplosyllis spongiphila (Verrill, 1885) (e. g. Blake, 1995). Additionally, Hartmann-Schröder described very similar species Typosyllis bifida from Southern Ocean, South Shetlands, 488m, which however lacks eyes.
