amaryllis?

[Anne Kilmer]

A huge family of caterpillars were brought in to the Mounts (West Palm
Beach, Florida) today, gathered from amaryllis. (She says they were also
eating grass, but I don't believe her.) 
They are black with white stripes around them; orange belly, smooth,
brown head and claspers ... green frass. No horn. Hundreds of them. We
assume it's a moth. 
Paul Pfenninger is rearing some, but, meanwhile, we'd like to know ... 
Anybody happen to know what we have here? 
Alas, Tom Emmel was here last night, but he's gone. Oh well.
Anne Kilmer
South Florida