Stiliger fuscovittatus Lance 1962

As a Sacoglossan, this nudibranch-like species has no external shell nor cephalic shield. Rhinophores, if present, are solid or rolled, not perfoliate, with longitudinal ridges, or with vertical pinnate plumes, and the clavus is not distinct from the stalk. Rhinophores, if present, cannot be retracted into a sheath. The dorsum of Sacoglossans may or may not have elongated outgrowths such as cerata. The anus is on the dorsal midline, just posterior to the rhinophores. Stiliger fuscovittatus has cerata and well-developed, simple, solid, tapered rhinophores but the foot is not expanded into parapodia. The large cerata are on both the anterior and posterior half of the dorsum. The body is approximately cylindrical, and the posterior foot tapers back to form a pointed tail. The cerata and the dorsum have a reddish-brown pattern of spots and irregular lines on a grayish-white background. Some references say that two reddish-brown lines run posteriorly from the rhinophores and others say there may be a brownish line running down the rhinophore stalk and forward between the eyes. These features were not seen on this individual. Total length up to 8-10 mm.

How to Distinguish from Similar Species: Hermaea oliviae, Hermaea vancouverensis and Placida dendritica have rolled rhinophores. Alderia modesta has no rhinophores. Placida dendritica has up to 50 cerata, which have green extensions of the gut into them.

On filamentous red algae, mainly in bays.

Geographical Range: Ketchikan, Alaska to Bahia de Los Angeles, Baja California, Mexico

Biology/Natural History: Usually found on the red alga Microcladia or sometimes other filamentous red algae. Can be abundant, especially in April-June. The eggs are laid in spiral strings with individual sausage-shaped sections in late spring-summer.