Nereis diversicolor

Chris Barrett Hello my friends. Today, I was examining the stomach contents of a viviparous blenny/eelpout (Zoarces viviparous). I came across what's shown in the attached photo, which to me, looked like a squid beak and mantle. Does anyone agree? If so, I've never come across squid jaws with serrated edges before

Chris Barrett Nereis jaws?

David Fenwick Snr Yes Chris I'd go with that, first thing I thought of when I looked. An isopod like Sphaeroma for the larger piece anyone ? A huge stab in the dark though.

Sabine Katharina Wieczorek Chris is right. I analysed the stomach contents of snow crabs for a year - that's exactly what they are.

Sabine Katharina Wieczorek Polychaete mouth parts.

Sabine Katharina Wieczorek check out Fauchald "the polychaete worms"

Chris Barrett Thanks all. Credit to Seamus Whyte for giving me the answer. Sabine, I will check that out, thank you for the tip! :) Happy Christmas, all!

Andy Horton A Wheeler says it feeds on small crustaceans, occasional fish and molluscs. So can be add polychaetes or worms to the list? Or just occasionally? I would not find committing myself to the guess that worms form an important part of its diet ??? A Wheeler is likely to be quite accurate for the diet of the British fishes (from past experience).

Chris Barrett Thanks for the info, Andy. I also found Scololepsis squamata (whole) inside of a long spined scorpion fish from the same site too. When my diet papers have been written and checked, I will forward them to you. Hopefully some of the prey items might be of interest to you. At the moment, I'd say worms are part of the diet, albeit in very small, insignificant quantities.

Chris Barrett Just had another S.squamata inside Ciliata mustella. From this sample (winter from North Yorkshire), species of Idotea seem to be the major food items in Lipophrys pholis, Taurulus bubalis and Ciliata mustella

Andy Horton Do you do aquarium studies? When you have a list I would be interested in filing diets of rock pool fish

Andy Horton http://www.glaucus.org.uk/fishdata.htm Index page.

Chris Barrett I'm studying for a PhD in marine biology/ecology. I'm looking at coexistence of intertidal fishes in the UK, so I look at things like habitat preference, distribution and co-occurence, dietary preference, etc., so yes, I will have a list when i'm done and would be happy to send it to you.

Andy Horton Diet varies according to location and time of year. T bubalis has a tremendous appetite and it would need to eat a hell of a lot of Idotea to satisfy its belly. Type of teeth is an interesting contrast between the fish mentioned.

Chris Barrett I've made notes in dentition, but haven't really done much else with them. Like you say though, teeth are interesting. I've been doing dietary comparisons between shores, seasons and fishes, so getting a nice data set from it all. I've collected specimens from three sites on the north yorkshire coast and three sites around the Isle of Anglesey. Already, the differences between Anglesey and North Yorkshire are noticeably different, as is the diet composition between summer and winter. Very interesting stuff!

Andy Horton I have been to Cullercoats beach and I remember noting the prevalence of Idotea and the surprising absence of a Palaemon. But this was just one summer visit.

Douglas Herdson Hi Chris, definitely errant polychaete jaws. They look slightly different to the Nereis diversicolor (now Neanthes?) from the Tees estuary that I was working on in redshank gut contents forty years ago but that could just be my memory. You can find the mass of the worms eaten by measuring the width (widest) of the jaws with a micrometer and calibrate this against the jaws and masses of worms you collect.