"Glossodoris symmetrica always also has blood-red rhinophores and gills like this photo. The blotches on the centre of the mantle (which are cream-coloured to almost dull yellow) are not quite as distinct at the edges as the white ones in Glossodoris pallida so they seem more like smudges than blotches, but nonetheless they are always present."
Comment from Richard Willan
Glossodoris symmetrica always also has blood-red rhinophores and gills like this photo. The blotches on the centre of the mantle (which are cream-coloured to almost dull yellow) are not quite as distinct at the edges as the white ones in Glossodoris pallida so they seem more like smudges than blotches, but nonetheless they are always present.