This large, common, and variable cephalaspidean is observed often around the Channel Islands. This large cephalaspidean is a voracious eater of opisthobranch mollusks. Many photos are included below to show the variation in color.
The spotted one below also resembles Navanax polyalphos, which has been suggested to be synonymous. I think the jury is still out.
This medium sized individual was observed to stalk and attack a smaller slug of the same species.
A muck site near Pelican Landing, Santa Cruz, was occupied by many very large individuals at least 150mm in length, mating and eating bubble shells Bulla gouldiana.
Created 15 November 2008
Updated 15 September 2025
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