Plumalina n. sp.
Late Devonian
Yukon Territory United States

Enormous 420mm problematica on 430mm x 380mm slab. May be the largest ever found.

Plumalina is a fossil known since the 1850’s, but exactly what it is has remained mysterious. It is often regarded as a hydrozoan (phylum Cnidaria, class Hydrozoa) or a gorgonarian (phylum Cnidaria, class Anthozoa, order Gorgonaria), but Plumaria possesses a variety of features that make either of these assignmants uncertain.

See: Wikipedia – Hydrozoa