Crustose

A crustose lichen, Caloplaca marina

Crustose is a habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. Crustose adheres very closely to the substrates at all points. Crustose is found on rocks and tree bark.[1] Some species of marine algae of the Rhodophyta, in particular members of the order Corallinales, family Corallinaceae, subfamily Melobesioideae with cell walls containing calcium carbonate grow to great depths in the intertidal zone, forming crusts on various substrates.[2] The substrate can be rocks throughout the intertidal zone, or, as in the case of the Corallinales, reef-building corals, and other living organisms including plants, such as mangroves and animals such as shelled molluscs. The coralline red algae are major members of coral reef communities, cementing the corals together with their crusts. Among the brown algae, the order Ralfsiales comprises two families of crustose algae.[3]

  1. ^ Biology Lab Manual 1110. ISBN 9781285111230.
  2. ^ Lee, Robert Edward (2008). Phycology (4th ed.). Cambridge University Press. ISBN 9780521682770.
  3. ^ Lim, P.-E.; M. Sakaguchi; T. Hanyuda; K. Kogame; S.-M. Phang; H. Kawai (2007). "Molecular phylogeny of crustose brown algae (Ralfsiales, Phaeophyceae) inferred from rbcL sequences resulting in the proposal for Neoralfsiaceae fam. nov". Phycologia. 46 (4): 456–466. doi:10.2216/06-90.1. S2CID 51999619.