We saw these at Mainit and Secret Garden. There seems to be a fine line between Goniobranchus rufomaculatus and G. aureopurpureus, but our specimens of the former from the Marshall Islands have white or translucent gills.
We think the left specimen below is a juvenile Goniobranchus aureopurpureus. The one on the right might be a young Goniobranchus alius.
Created 15 June 2015
Updated 17 June 2020