larva• There will be larvae too, but these are small and go through the sieve.• The sea squirtlarva is not the only filter-feeder with such a significantrod in its back.• There are three stages - larva, nymph and adult - each of which quite often feeds off a different host.• At higher temperatures, development is faster and the larvae are hyperactive, thus depleting their lipidreserves.• Escamoles are the larva and pupa stage of the red ant.• This, at least, is some suggestion of a backbone, but the larva does not keep it for very long.• Growth is rapid, on a diet of tinylarvae, worms and relatives.• The eggs sit all winter, but don't turn to larvae until there's a rain.