| Goniodoris, Rostanga rubra, Geitodoris planata, Jorunna tomentosa, Polycera quadrilineata|
Goniodoris castanea is a species of sea slug, a dorid nudibranch, a marine gastropod mollusc in the family Goniodorididae.
Goniodoris castanea Wikipedia
This species was first described from Salcombe Estuary, Devon. It has subsequently been reported widely in Britain and Ireland and from Norway to the Mediterranean Sea.
This goniodorid nudibranch is variable in colour, usually red-brown or dark purple but also bright red. Most individuals have scattered irregular small patches of white or grey all over the body.
Goniodoris castanea feeds on tunicates of the genera Botryllus and Botrylloides, family Botryllidae.