Worldwide: Nova Scotia, Western Atlantic, Canada to Florida. Gracilaria verrucosa Gracilaria verrucosa (Hudson) Paperfuss Characteristics Plants bushy, 1-3dm tall, with age often becoming free, texture firmly fleshy, colour dull purplish, grayish or grenish translucent, branches 0.5-2 mm diameter, repeatedly dividing, alternately or occasionally dichotomously branched with numerous lateral proliferations, terete throughout, tapering to the ultimate branchlets, cells of the medulla 300-450 micron diameter, with rather thin walls, cortex of 2-3 layers of small cells, tetrasporangia numerous, scattered over the branchlets, oval, from the surface 22-30 micron diameter, in section 30-33 micron long, cystocarps very prominent, often numerous. Distribution :Okha,(Gujrat) Bombay,(Maharashtra) Goa . Ecological status : Mangrove swamps, brackish water. IUCN status : EN Uses : It is used as raw material for agar manufacture. It is also eaten raw as salad or cooked with vegetables, animal feed. Halimeda copiosa1 Large-leaf hanging vine Halimeda copiosa Goreau & Graham, 1967 Description: Plants form long chains of rectangular-shaped, relative large, leaf-like, calcified segments, which are held together by a thin strand running through their centers. Strands may branch frequently and may reach a length of 60 cm. Segments green to yellowish green on top, underside often lighter. Segments nearly 2 cm in width. Habitat: Tend to grow in shaded areas of the reef, often hanging from ledge undercuts and along walls, down to 60 m. Distribution: Abundant to common South Florida, Bahamas and Caribbean. Halimeda discoidea Halimeda Taenicole Halimeda is a calcareous green algae of siphonous construction forming a coencytic 3D structure consisting of interwoven filaments. Put simply Halimeda is a giant web of strings of cells that are joined together to form a large semi-rigid structure. The taxonomic classification of Halimeda places it under the same class and order as the prolific Caulerpa (an invasive species that is causing havoc in tropical areas), but divides into the family Halimediaceae. There are around 25-30 species of Halimeda, this figure varies by the indices used for identification and the species definition used. Most species are exclusively marine, with one single freshwater species (see quote). Halimeda copiosa | Halimeda cryptica | Halimeda cylindracea | Halimeda discoidea | Halimeda gigas | Halimeda goreauii | Halimeda gracilis | Halimeda hummii | Halimeda incrassata | Halimeda incrassata | Halimeda lacrimosa | Halimeda macroloba | Halimeda macrophysa | Halimeda magnidisca | Halimeda melanesica | Halimeda monile | Halimeda opuntia | Halimeda scabra | Halimeda simulans | Halimeda taenicola | Halimeda tuna | Halimeda velasquezii Members of the Halimeda genus are very distinct. Commonly called the money plant as it is reminiscent of numerous small coins joined end to end. Scientifically the plant is recognisable by the entire plants being comprised of numerous flat segments ranging between 0.5 cm to 5 cm in diameter. The structure is semi-rigid with each segment being calcified in the form of calcium carbonate aragonite crystals and connected together via uncalcified flexible nodes (aka geniculae). The holdfast system of Halimeda is psammophytic (see picture below). The root like holdfast can attach in almost any benthic substrate such as mud / loose sand or rock, this gives Halimeda a tremendous advantage over other species of algae and is the main factor behind the colonisation of bare areas by Halimeda species. The presence of hard calcium carbonate within the tissues make the plant inedible to most herbivores. Although calcification is a useful adaptation it does have problems, for instance if the plant was entirely calcified, wave action and collisions with water borne particles or pelagic organisms could break parts of the plant off with very little energy. Also ocean acidification could pose a threat in the near future. The adaptation of having a partially calcified structure is not specific to Halimeda, other algae such as Corallina offiincialis has also evolved this adaptation. This algae is capable of living under low-moderate light, it will grow strongest in moderate to high lighting. All macros present some risk of going sexual and releasing carbon dioxide into you aqaurium. However, the risk of adverse ph changes from the release of carbon from this species is extremely low. Because this plant uses calcium to grow, you should keep your tank within 350-450 ppm of calcium for best results.