Community hub
Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
Coralline algae
Coralline algae are red algae in the order Corallinales, characterized by a thallus containing calcareous deposits within its cell walls, giving it hardness. The colors of these algae are typically some hue of pink, or another shade of red, but some species can be purple, yellow, blue, white, or gray-green. Typically, these algae grow in a crustose manner (encrusting rocks and other hardscape); in the intertidal zone of rocky shorelines, and within coral reefs, these algae appear as an abundance of colorful patches on rock surfaces. Unattached specimens (maerl, rhodoliths) may form relatively smooth compact balls, or forming warty to fruticose thalli.
The red algae belong to the division Rhodophyta, within which the coralline algae form the order Corallinales. There are over 1600 described species of nongeniculate coralline algae. The corallines are presently grouped into two families on the basis of their reproductive structures. Most are marine, though one species lives in freshwater; Pneophyllum cetinaensis.
Coralline algae play an important role in the ecology of coral reefs. Sea urchins, parrot fish, along with limpets and chitons (both mollusks) feed on coralline algae. In the temperate Mediterranean Sea, coralline algae are the main builders of a typical algal reef, the Coralligène ("coralligenous").
Corallines have been divided into two groups based on their growth forms, although this division does not conform to taxonomic grouping:
Geniculate corallines are branching, tree-like organisms which are attached to the substratum by being crustose or possessing calcified, root-like holdfasts. The organisms are made flexible by having non-calcified sections (genicula) separating longer calcified sections (intergenicula). Nongeniculate corallines range from a few micrometres to several centimetres thick crusts. They are often very slow growing, and may occur on rock, coral skeletons, shells, other algae or seagrasses (being epiphytes). Crusts may be thin and leafy to thick and strongly adherent. Some are parasitic or partly endophytic on other corallines. Many coralline crusts produce knobby protuberances ranging from a millimetre to several centimetres high. Some are free-living as rhodoliths (rounded, free-living specimens). The morphological complexity of rhodoliths enhances species diversity, and can be used as a non-taxonomic descriptor for monitoring.[clarification needed]
Corallines, especially encrusting forms, are slow growers, and expand by 0.1–80 millimetres (0.0039–3.1496 in) annually. All corallines begin with a crustose stage; some later become frondose.
The thalli can be divided into three layers: the hypothallus, perithallus and epithallus. The epithallus is periodically shed, either in sheets or piecemeal.
Since coralline algae contain calcium carbonate, they fossilize fairly well. They are particularly significant as stratigraphic markers in petroleum geology. Coralline rock was used as building stone since ancient Greece.
Hub AI
Coralline algae AI simulator
(@Coralline algae_simulator)
Coralline algae
Coralline algae are red algae in the order Corallinales, characterized by a thallus containing calcareous deposits within its cell walls, giving it hardness. The colors of these algae are typically some hue of pink, or another shade of red, but some species can be purple, yellow, blue, white, or gray-green. Typically, these algae grow in a crustose manner (encrusting rocks and other hardscape); in the intertidal zone of rocky shorelines, and within coral reefs, these algae appear as an abundance of colorful patches on rock surfaces. Unattached specimens (maerl, rhodoliths) may form relatively smooth compact balls, or forming warty to fruticose thalli.
The red algae belong to the division Rhodophyta, within which the coralline algae form the order Corallinales. There are over 1600 described species of nongeniculate coralline algae. The corallines are presently grouped into two families on the basis of their reproductive structures. Most are marine, though one species lives in freshwater; Pneophyllum cetinaensis.
Coralline algae play an important role in the ecology of coral reefs. Sea urchins, parrot fish, along with limpets and chitons (both mollusks) feed on coralline algae. In the temperate Mediterranean Sea, coralline algae are the main builders of a typical algal reef, the Coralligène ("coralligenous").
Corallines have been divided into two groups based on their growth forms, although this division does not conform to taxonomic grouping:
Geniculate corallines are branching, tree-like organisms which are attached to the substratum by being crustose or possessing calcified, root-like holdfasts. The organisms are made flexible by having non-calcified sections (genicula) separating longer calcified sections (intergenicula). Nongeniculate corallines range from a few micrometres to several centimetres thick crusts. They are often very slow growing, and may occur on rock, coral skeletons, shells, other algae or seagrasses (being epiphytes). Crusts may be thin and leafy to thick and strongly adherent. Some are parasitic or partly endophytic on other corallines. Many coralline crusts produce knobby protuberances ranging from a millimetre to several centimetres high. Some are free-living as rhodoliths (rounded, free-living specimens). The morphological complexity of rhodoliths enhances species diversity, and can be used as a non-taxonomic descriptor for monitoring.[clarification needed]
Corallines, especially encrusting forms, are slow growers, and expand by 0.1–80 millimetres (0.0039–3.1496 in) annually. All corallines begin with a crustose stage; some later become frondose.
The thalli can be divided into three layers: the hypothallus, perithallus and epithallus. The epithallus is periodically shed, either in sheets or piecemeal.
Since coralline algae contain calcium carbonate, they fossilize fairly well. They are particularly significant as stratigraphic markers in petroleum geology. Coralline rock was used as building stone since ancient Greece.