CorallineAlgae

Coralline Algae

Description

Coralline algae are usually pink or red, but they can be other colors as well, including gray, green, blue, yellow, and purple.

This alga takes two main morphological forms. These forms are called branching (geniculate or articulated) and encrusting (non-geniculate or non-articulated). The branching form protrudes from the substrate on which the alga is situated whereas the encrusting form grows along the surface of the substrate.

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Classification

Kingdom: Protista

Division: Rhodophyta (red algae)

Class: Rhodophyceae

Subclass: Florideae

Order: Corallinales

Family: Coralinaceae (Coralline algae)

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Habitat/Location

Coralline algae inhabit intertidal and subtidal coastal areas. It is necessary for the algae to perform photosynthesis, so the algae's habitat is limited to the depth of light penetration in water (depth of 0-270 meters). Because coralline algae is crucial for the construction of reefs, this partly explains why reefs are predominantly found in shallow depths of water.

Non-geniculate algae must live on an area that provides them with support. They are most commonly found on bedrock in the ocean, but they can also live on other types of substrate, such as an animal shells or on top of other algae. Geniculate algae also commonly live on substrates, but unlike non-geniculate algae they have the ability to be partially unattached. As long as they are anchored so some part of the substrate, the rest of the algae can be independent.

Algae can tolerate varying levels of water salinity. They do not live in freshwater; only in salinated water. Coralline algae can also be found in aquariums. The alga are popular accessories for decorative or functional tanks.

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Biology

can perform sexual or asexual reproduction

mineralogy: calcite (calcium carbonate, CaCO3)

this compound sometimes contains Mg as well

fouling: sloughing off outer layer of cells

coralline algae performs fouling in order to compete with algae attempting to grow on top of preexisting coralline algae, eliminate burrowing organisms in outer layer, and renew damaged tissue and reproductive cells

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Ecology

typically epiphytes

promote herbivores and invertebrates by producing chemicals that attract herbivore larval settlement, and by providing habitat for small reef animals and invertebrates

parrot fish and mollusks eat coralline algae

calcite production binds reefs together and is crucial to the structure of reef systems

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Environmental Significance

useful for fossil dating

commonly found on reefs, but reefs are becoming endangered

extracted for economic use-- geniculate algae are especially targeted

used for soil conditioner, animal food additive, pharmaceutical products

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Sources

Cabioch, J. "Morphogenesis and Generic Concepts in Coralline Algae — a Reappraisal." Helgoländer Meeresuntersuchungen Helgolander Meeresunters 42.3-4 (1988): 493-509. Web.

"Coralline Algae." Coralline Algae. California State University, Fullerton, n.d. Web. 01 Mar. 2016

Johansen, H. William. Morphology and Systematics of Coralline Algae with Special Reference to Calliarthron. Berkeley: U of California, 1969. Print.

Keats, D.w., M.a. Knight, and C.m. Pueschel. "Antifouling Effects of Epithallial Shedding in Three Crustose Coralline Algae (Rhodophyta, Coralinales) on a Coral Reef." Journal of Experimental Marine Biology and Ecology 213.2 (1997): 281-93. Web.

Martin, Sophie. "Marine Coralline Algae." Marine Coralline Algae. The Encyclopedia of Earth, 15 June 2014. Web. 01 Mar. 2016.

Steneck, R. "The Ecology of Coralline Algal Crusts: Convergent Patterns and Adaptative Strategies." Annual Review of Ecology and Systematics 17.1 (1986): 273-303. Web. 1 Mar. 2016.

Woelkerling, W. J. M.H. Foslie and the Corallinaceae: An Analysis and Indexes. Vaduz: J. Cramer, 1984. Print.