Catriona aurantia (Alder & Hancock, 1842)
1) Translucent smooth rhinophores tinted orange-brown.
2) Cerata not crowded and do not extend forwards of rhinophores.
3) Powdery opaque white covers distal part of cerata; more extensive and prominent than on C. nana.
4) Does not feed on Hydractinia echinata.
Length 16 mm. LWST, Menai Strait, Wales. March 2011.