Musculus subpictus

Paula Lightfoot Is this Musculus subpictus? 2.5mm long from Strangford.

Ian Smith Yes, it's a well marked Musculus/ Modiola/ Modiolarca/ Modiolus/ Mytilus tumida/ subpicta/ subpictus/ marmoratus - just too many changes in my lifetime :-(

Simon Taylor Hi Paula. Did you ever check that Strangford specimen which looked like a juvenile discors?

Paula Lightfoot thanks Ian glad you mentioned the confusion of names, I was looking for records on the Gateway and couldn't find any - I only looked for Modiolarca subpicta and Musculus subpictus, I see there are a few others I should check! Simon I think this photo is discors, 8mm would that make it a juvenile?

Paula Lightfoot and the other side

Simon Taylor Hmmm, actually the shape of that looks more like subpicta than discors. And I think the specimen I recall was smaller than 8mm. Have you counted the ribs on this one? Shape can be a little confusing in subadult specimens.

Ian Smith I agree with Simon, this is subpictus/a , but at 8mm it is a fully functioning adult. Here's a picture of one 2mm long expelling ova I THINK; perhaps they have strange pooh. I can't find any text saying it has fertilization in the mantle cavity and expels ova in clumps; can anyone help with a link to an accessible online text giving details that I don't have to pay £30 to view?

Paula Lightfoot I only have three specimens (2.5mm, 6.5mm and 8mm) and looking at them together under the microscope they all look VERY similar - so probably all subpictus. I will post a photo of all three and try to count the ribs but I'm busy at work this week and away to Scotland at the weekend, but I will come back to these little shells eventually...