Rostanga pulchra MacFarland, 1905
Common name(s): Red sponge nudibranch, Red sponge doris, Red nudibranch, Crimson doris
|Rostanga pulchra, approximately 1 cm long, on a sponge at Swirl Rocks|
|(Photo by: Dave Cowles July 2005)|
How to Distinguish from Similar Species: Aldisa sanguinea, which lives from Oregon to Baja California and also feeds and lives on red sponges, has perfoliate rhinophores.
Geographical Range: Point Craven, Alaska to the Gulf of California; Chile, Argentina
Depth Range: Intertidal to 102 m
Habitat: On and around red sponges
Biology/Natural History: This species
feeds on, and is often found on, red sponges such as Acarnus,Esperiopsis,Ophlitaspongia,
and Plocamia. It lays
its eggs in a tight orange circle on the sponges March to October (photo).
The larvae are planktonic for 30-45 days, then settle. An encounter
with at least one prey sponge, Ophlitaspongia
pennata, can induce larvae to settle. It is believed that
its orange pigment comes from the sponge. Adults can locate and navigate
to distant Ophlitaspongia
sponges by smell. Some individuals seem to stay quite close to one
area while others range for distant sponges. Predators may include
the flatworm Notoplana acticola.
The cephalaspidean predatory nudibranch Navanax inermis is repelled by secretions from Rostanga.
|Main Page||Alphabetic Index||Systematic Index||Glossary|
Bruscaa nd Brusca, 1978
Johnson and Snook, 1955
Morris et al., 1980
O'Clair and O'Clair, 1998
Ricketts et al., 1985
General Notes and Observations: Locations, abundances, unusual behaviors:
This individual is crawling across red algae in a tidepool. Photo by Dave Cowles, July 2005
This 1/2 cm specimen was photographed by Dave Cowles at San Simeon, CA May 2001
This species lays red coils of eggs on the red sponge on which it feeds. Photo by Dave Cowles in a tidepool, July 2012
This pair of nudibranchs on a sponge near the one shown above with eggs are probably preparing to mate and lay eggs as well.