The cave-dwelling predators capture crustaceans under long by entangling them with fine threads , digest them by enveloping them with further threads over the course of a few days , and then return to their normal shape ; there is no evidence that they use venom .
The cave-dwelling predators capture crustaceans under 1 mm long by entangling them with fine threads , digest them by enveloping them with further threads over the course of a few days , and then return to their normal shape ; there is no evidence that they use venom .