aufwuchs

Etymology
Borrowed from.

Noun

 * 1) The small animals and plants that encrust hard substrates, such as rocks, in aquatic environments.

Usage notes

 * Aufwuchs may be used with plural verbs ("the aufwuchs are...") or singular verbs ("the aufwuchs is..."). Rarely, is used as a singular form, denoting a single small animal or plant that forms part of the aufwuchs.