Euclymeninae Arwidsson, 1906
Euclymeninae sp. 2
Voucher. ENDEAVOUR: station E4FA.
Diagnosis. Very slender species with very long segment (possibly damaged –stretched?); voucher is the only example collected; assumed incomplete as only 12 chaetigers present; posterior part possibly damaged (uncertain if true pygidium present); 18mm long and 0.3mm wide. Chaetiger very slender and long, chaetiger about 0.5mm long, chaetigers 2 – 4, around 1mm long, subsequent chaetigers >2mm long.
Prostomium fused to peristomium; cephalic plaque present, strongly arched, rounded anteriorly (not extended into palpode); with very low rim, anteriorly smooth; posteriorly somewhat crenulated; straight, anteriorly diverging nuchal organs in posterior part of prostomium. Eyes or ocelli not observed.
Notochaetae few (3-5? per fascicle), often broken off, at least 3 types observed: rather short spatula chaeta; long, thick, bilimbate chaeta with fine tip and short, thin, capillaries (about 1- 3 per fascicle).
Uncini present from chaetiger 1; all rostrate hooks; increasing in number from 3 in chaetiger 1 to up to 8 in mid-body chaetigers. Each uncinus with main fang and about 6 smaller teeth, without fibrils, but with a small hood below the main fang; long, bent shaft with a pronounced localized swelling (breast) in the middle.
Preanal segments not obvious. Pygidium (if real rather than damaged), very small, asymmetrical, with numerous, irregular, short, rounded lobes.
Remarks. Generic identity of this incomplete specimen is uncertain and we adopt a conservative approach to identifying it only to a sub-family. Voucher agrees with family Euclymeninae as it has a head with plaque, neurochaetae from chaetiger 1 and reduced in number in first 3 chaetigers. It is not clear if the specimen is complete, the posterior end is most likely damaged/regenerating.
