The mussel was approx 15cm long, with a blunt round umbo.
No interactions present.
I agree it is dead mens fingers, but that's a soft coral (Cnidarian) not a sponge. What an interesting thing to find!
and yes it isn't a sponge but a coral as Paula quite rightly points out :)
All very interesting. Thank you.
...trimming your photo and adding Alcyonium on it's own as probably not too many people have seen this cnidarian before.
A good find. There are some lovely photos of the polyps extended in water at
Lat/Lng: 57.876, -4.014
OS grid ref: NH806891