By only worry is... what kind of butterfly will they turn
into... 
SLOW FOOD. Hawaiian caterpillar (arrow) pokes out of its mottled
gray case to wrap silk around a snail.
The Caterpillar Gets Inside the Shell
A type of caterpillar with a taste for escargot rather than the
normal vegetable diet has been discovered in Hawaii. The
caterpillar is the first ever observed to eat any kind of mollusk,
researchers report in Friday's issue of the journal Science.
Indeed, only about one-tenth of 1% of caterpillars eat anything but
vegetables.
Hyposmocoma molluscivora, however, will not eat the green stuff
even when the caterpiller is starving, say Daniel Rubinoff and
William Haines of the University of Hawaii, Honolulu.
When these caterpillars come across a resting snail, they begin
spinning silk of the type they use to make their cocoons. They wrap
the silk around the snail, trapping it so the snail cannot escape
by dropping off the leaf.
Then, the researchers say, it's snail-snacking time.
"They wrap 'em, up and then they go in, the snail doesn't really
have a chance," Rubinoff said in a telephone interview.
The caterpillar "wedges its case next to or inside the snail shell
and stretches much of its body out of the silk case, pursuing the
retreating snail to the end of the shell from which there is no
escape," Haines and Rubinoff report.
The researchers observed 18 different snail attacks by 10 different
caterpillars.
The snails they studied were on Maui, but Rubinoff said others have
since been found on three other Hawaiian islands Molokai, Hawaii
and Kauai.
A few caterpillars have been found to eat scale and other small
insects but moving on to snails is a big shift, he said.
"I don't think we have any idea how something like that happens,"
Rubinoff said when asked how these caterpillars might have started
on such a diet. "It's one of the things that makes Hawaii such a
great place to do this research," he said, adding that there are
probably a lot more unusual creatures waiting to be
discovered.
Finding something like this "just never occurred to us," Rubinoff
said. "Just because we didn't think of it doesn't mean its not
right there."
