Photo license and credit, and taxonomic work, belongs to the Florida Museum of Natural History (FLMNH).
This observation is a part of the long-term monitoring efforts of Gustav Paulay and his team at FLMNH and Friday Harbor Labs.
6mm length. Taken in bottom grab in 62.5m depth. Scanned from 35mm slide. Figure 11B in Valdes, 2019, Northeast Pacific benthic shelled sea slugs. Zoosymposia 13: 242–304.