Fossils ID, Cornwall spine?

[Gully.moy]

A couple of spiny looking fossils in hard rock in Carlyon bay, Cornwall, near St. Austell. I know nothing about fossils so any input appreciated :-)

[TqB]

Hi, those are nice and clear and you'd think it would be easy!

 

I suspect they're trace fossils - burrowing traces of some sort. The rocks are Lower Devonian siltstones, Meadfoot Beds. They do contain a sparse invertebrate fauna in places of trilobites, brachiopods, corals etc. but these don't match what you've got.

Trace fossils listed for the beds elsewhere include Spirophyton, which is at least reminiscent of your second one. There are many other possibilities and we probably need an ichnofossil specialist! (Spirophyton is actually no longer formally available as an ichnogenus but is still widely used.)

 

(There are also fish beds around there but I don't believe these are related.)