Hawaii is a beautiful tropical paradise and also home to formidable creepy crawly predators. There are spiders that impale prey in midair and venomous centipedes that can stretch nearly 15 inches long.

And then there are the carnivorous caterpillars, an evolutionary rarity. And now scientists have discovered one very hungry caterpillar that doesn’t just eat other insects — it decorates itself in the macabre mishmash of the body parts of its meals.

Nicknamed the bone collector, this caterpillar and its grisly taste in couture are described Thursday in the journal Science. “This behavior was utterly unknown,” said Daniel Rubinoff, an entomologist at the University of Hawaii at Manoa and an author of the study. His team initially compared the caterpillars to crawling crime scenes.

The bone collector caterpillar is found only within a six-square-mile swath of a single mountain range on the island of Oahu. There it resides exclusively on cobwebs spun by spiders in logs and rock cavities. As the caterpillars skulk about the webs, they scavenge dead and dying insects and other arthropods ensnared in the sticky silk.

According to David Wagner, an entomologist at the University of Connecticut who was not involved with the new study, the caterpillar’s reliance on spiders presents one of nature’s most improbable connections. “It is remarkable that a caterpillar would tie its fate to a spider — a clear and present danger for both caterpillar and moth alike,” Dr. Wagner said. He’s aware of only one other moth species that frequents spider webs. But that species is a vegetarian that snacks on plant material caught in the web.

Dr. Rubinoff first encountered the bone collector caterpillar in 2008 when he examined a web inside a tree hollow. The caterpillars are incredibly rare. More than 150 field surveys in the area have yielded only 62 bone collector specimens.