Roboastra tigris

Roboastra tigris Farmer, 1978

At the risk of exaggeration, this is one mean slug! It has been reported from offshore islands in the central and southern Gulf of California (Islas San Pedro, Monserrate and San Diego, near Guaymas; and islands in the region of Bahia de los Angeles and La Paz), usually below 50 feet (about 16m) deep.

Its predominant body color is a greenish, yellow-ochre, with five longitudinal dark navy blue stripes outlined by light green. The rhinophores and oral processes are blue-black. The gills are blue-black distally, with light green bases. Adults range from 3 to 12 inches (75-300mm) in total length.

Roboastra tigris is a voracious predator, It will survive well in an aquarium on a steady diet of other nudibranchs. Species of tambja seem to be its preferred prey, but other dorids and eolids are also accepted. Robastra follows the slime trail of its predators. When its projecting chemosensory/tactile "bumpers" (oral processes) contact a potential prey item , its oral veil explodes out of its mouth, engulfing the prey . The hapless slug is engulfed by this brilliant blue canopy and grappled down Roboastra's throat by the meat-hook-shaped radular teeth.

Provided with fresh nudibranchs (non-sponge eating species) it will survive well in an aquarium, Its lifespan is probably a year but attentive care might extend that.

Text courtesy of:

Dr. Hans Bertsch

Assoc. Prof.
Dept. of Math and Natural Sciences
National University
192 Imperial Beach Blvd. #A
Imperial Beach, CA 91932
FAX (619) 423-9118
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