[Annelida] Oligochaete with anal cirri?

[Geoff Read]

Dear all,

Quick question? Do oligochaetes ever have a pair of anal cirri?  I have been looking at offshore samples from mobile coarse sands with some interesting small worms in them, and there is this apparent oligochaete (or not) which has a lovely pair of delicate anal cirri.  It has a long prostomium, or perhaps it's the pygidium if I've oriented it wrong way round (it's hard to say), is exceedingly thin (0.15 mm w, & TL 10 mm) like a marine oligochaete, has mixed capillaries and slightly thicker shorter unifid S-shaped single chaetae.  What do you reckon it could be if not an oligochaete?  There are no tentacles along the body (as in cirratulids and affiliates). There is a polygordiid genus which has chaetae, but apparently not along the whole body as this worm has.

Thanks in advance for your ideas to enlighten me.

Geoff Read



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