Actually, not genus Grammia at all.
Formerly placed in genus Apantesis.
Still, quite vividly a member of Sly and the family Arctiidae. Or is it Arctiinae now... ah, the excruciating joys of entomological taxonomy.
Thanks to the collective and helpful knowledge-base at bugguide.net I have finally learned the currently true name of a tiger-moth I came across while still slingin' shrikes on Naval Auxiliary Landing Field, San Clemente Island.
The photos of this beast had been in a photo-dump file I honestly had forgotten about, until thinking of this particular individual.
Notarctia proxima "Mexican Tiger Moth"
This insect occurs from south-central Oregon down through California, Mexico and Central America. Also occurring west to east from Nevada, Utah, far west Colorado, south-central New Mexico, and the Big Bend region of far west Texas.
Hindwing color can vary from mostly white to mostly red.
Abdomen red or orangish with black tip.
Anyways, this individual was pointed out to me early one morning, 19 Oct 2008, by US Navy personnel . It was recently deceased on the inside window ledge of the SCI security building.
That building had great porch/security lights.
Anyhow, the "Woolly Bear" - type caterpillars that some may recall are generally "Tiger Moth" species.