A few species of Lepidoptera are secondary consumers, or predators. These species typically prey upon the eggs of other insects, aphids, scale insects, or ant larvae. Some caterpillars are cannibals, and others prey on caterpillars of other species (e.g. Hawaiian "Eupithecia" ). Those of the 15 species in "Eupithecia" that mirror inchworms, are the only known species of butterflies and moths that are ambush predators. Four species are known to eat snails. For example, the Hawaiian caterpillar ("Hyposmocoma molluscivora") uses silk traps, in a manner similar to that of spiders, to capture certain species of snails (typically Tornatellides).