Trapania miltabrancha

The species name miltabrancha is based on the Greek words for 'red gill' because Gosliner & Fahey, who have recently "described" the Trapania, consider the species to have 'pale red gill leaves'.
Here's the Original Submission to the Sea Slug Forum

Unidentified Trapania from Tulamben
February 28, 2007
From: Brian Francisco>