Description: 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.
Although much of the descriptions fit this species well, this identification is still tentative since I see no reddish-brown lines behind the rhinophores or the lines down the rhinophores forward to between the eyes.
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.
Geographical Range: Ketchikan, Alaska to Bahia de Los Angeles, Baja California, Mexico
Depth Range: [Presumably intertidal and shallow subtidal]
Habitat: On filamentous red algae, mainly in bays.
found on the red alga Microcladia
or sometimes other filamentous red algae (such as Callithamnion
in Monterey Bay, CA). Can be abundant, especially in
The eggs are laid in spiral strings with individual sausage-shaped
in late spring-summer.
Kozloff, 1987, 1996
General Notes and Observations: Locations, abundances, unusual behaviors:
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Salish Sea Invertebrates web site provided courtesy of Walla