Caulerpa taxifolia | |
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Scientific classification | |
(unranked): | Viridiplantae |
Division: | Chlorophyta |
Class: | Ulvophyceae |
Order: | Bryopsidales |
Family: | Caulerpaceae |
Genus: | Caulerpa |
Species: | C. taxifolia |
Binomial name | |
Caulerpa taxifolia (M.Vahl) C.Agardh, 1817 [1] | |
Caulerpa taxifolia is a species of green seaweed, an alga of the genus Caulerpa , native to tropical waters of the Pacific Ocean, Indian Ocean, and Caribbean Sea. [2] The species name taxifolia arises from the resemblance of its leaf-like fronds [3] to those of the yew (Taxus). [ citation needed ]
A strain of the species bred for use in aquariums has established non-native populations in waters of the Mediterranean Sea, the United States, and Australia. [4] It is one of two species of algae listed in 100 of the World's Worst Invasive Alien Species compiled by the IUCN Invasive Species Specialist Group. [5]
C. taxifolia is light green [3] with stolons (stems) on the sea floor, from which sparsely-branched upright fronds of approximately 20–60 cm (8–24 in) in height arise. [6] Algae in the genus Caulerpa synthesize a mixture of toxins [7] termed caulerpicin, believed to impart a peppery taste to the plants. [8] The effects of the specific toxin synthesized by C. taxifolia, caulerpenyne, have been studied, [9] [10] with extracts from C. taxifolia being found to negatively affect P-glycoprotein-ATPase in the sea sponge G. cydonium. [11]
Like all members of the genus Caulerpa,C. taxifolia consists of a single cell with many nuclei. The algae has been identified as the largest known single-celled organism. [12] Wild-type C. taxifolia is monoecious. [13]
Caulerpa species are commonly used in aquaria for their aesthetic qualities and ability to control the growth of undesired species. [14] C. taxifolia has been cultivated for use in aquaria in western Europe since the early 1970s. [15] A clone of the alga that was resistant to cold was observed in the tropical aquarium at the Wilhelma Zoo in Stuttgart [16] and further bred by exposure to chemicals and ultraviolet light. [17] The zoo distributed the strain to other aquaria, including the Oceanographic Museum of Monaco. [16]
The aquarium strain is morphologically identical to native populations of the species. [3] However, a 2008 study found that a population of the aquarium strain near Caloundra, Australia exhibited markedly reduced sexual reproduction, with only male plants present during some reproductive episodes. [13] The aquarium strain can survive out of water for up to 10 days in moist conditions, with 1 cm fragments capable of producing viable plants. [18]
Outside its native range, C. taxifolia is listed as an invasive species. [19] [20] It is one of two algae on the list of the world's 100 worst invasive species compiled by the IUCN Invasive Species Specialist Group. [5] The species is able to thrive in heavily polluted waters, [21] possibly contributing to its spread in the Mediterranean. [22]
The presence of C. taxifolia in the Mediterranean was first reported in 1984 [23] in an area adjacent to the Oceanographic Museum of Monaco. [24] Alexandre Meinesz, a marine biologist, attempted to alert Moroccan and French authorities to the spread of the strain in 1989, [16] but the governments failed to respond to his concerns. [25] The occurrence of the strain is generally believed to be due to an accidental release by the museum, [3] [26] but Monaco rejected the attribution and instead claimed that the observed algae was a mutant strain of C. mexicana. [25] By 1999, scientists agreed that it was no longer possible to eliminate the presence of C. taxifolia in the Mediterranean. [25]
A study published in 2002 found that beds of Posidonia oceanica in the Bay of Menton were not negatively affected eight years after colonization by C. taxifolia. [27] Other published studies have shown that fish diversity and biomass are equal or greater in Caulerpa meadows than in seagrass beds [28] and that Caulerpa had no effect on composition or richness of fish species. [29]
Studies in 1998 [15] and 2001 [23] found that the strain observed in the Mediterranean was genetically identical to aquarium strains, with similarities to an additional population in Australia.
A 2007 study found that a native bivalve mollusc species was negatively affected by the presence of C. taxifolia, but that the effect was not necessarily different from that of native seagrass species. [30] A 2010 study indicated that the effect of detritus from C. taxifolia negatively impacted abundance and species richness. [31]
C. taxifolia was found in waters near San Diego, California, in 2000, [32] where chlorine bleach was used in efforts to eradicate the strain. [33] The strain was declared eradicated from Agua Hedionda Lagoon in 2006. [34] California passed a law in 2001 forbidding the possession, sale, transport, or release of Caulerpa taxifolia within the state. [35] The Mediterranean clone of C. taxifolia was listed as a noxious weed in 1999 [36] by the Animal and Plant Health Inspection Service, prohibiting interstate sale and transport of the strain without a permit under the Noxious Weed Act and Plant Protection Act. [24] [37]
C. taxifolia may become entangled in fishing gear and boat propellers. [4]
C. taxifolia may be controlled via mechanical removal, poisoning with chlorine, or application of salt. [6] Researchers at the University of Nice investigated possible use of a species of sea slug, Elysia subornata , as a possible natural control method, but found that it was not suitable for use in the Mediterranean due to cold winter water temperatures and insufficient population density. [38]
Algae are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular microalgae, such as Chlorella, Prototheca and the diatoms, to multicellular forms, such as the giant kelp, a large brown alga which may grow up to 50 metres (160 ft) in length. Most are aquatic and lack many of the distinct cell and tissue types, such as stomata, xylem and phloem that are found in land plants. The largest and most complex marine algae are called seaweeds, while the most complex freshwater forms are the Charophyta, a division of green algae which includes, for example, Spirogyra and stoneworts. Algae that are carried by water are plankton, specifically phytoplankton.
An algal bloom or algae bloom is a rapid increase or accumulation in the population of algae in freshwater or marine water systems. It is often recognized by the discoloration in the water from the algae's pigments. The term algae encompasses many types of aquatic photosynthetic organisms, both macroscopic multicellular organisms like seaweed and microscopic unicellular organisms like cyanobacteria. Algal bloom commonly refers to the rapid growth of microscopic unicellular algae, not macroscopic algae. An example of a macroscopic algal bloom is a kelp forest.
Coralline algae are red algae in the order Corallinales. They are characterized by a thallus that is hard because of calcareous deposits contained within the cell walls. The colors of these algae are most typically pink, or some other shade of red, but some species can be purple, yellow, blue, white, or gray-green. Coralline algae play an important role in the ecology of coral reefs. Sea urchins, parrot fish, and limpets and chitons feed on coralline algae. In the temperate Mediterranean Sea, coralline algae are the main builders of a typical algal reef, the Coralligène ("coralligenous"). Many are typically encrusting and rock-like, found in marine waters all over the world. Only one species lives in freshwater. Unattached specimens may form relatively smooth compact balls to warty or fruticose thalli.
Caulerpa is a genus of seaweeds in the family Caulerpaceae. They are unusual because they consist of only one cell with many nuclei, making them among the biggest single cells in the world.
The Oceanographic Museum is a museum of marine sciences in Monaco-Ville, Monaco. This building is part of the Institut océanographique, which is committed to sharing its knowledge of the oceans.
Ascophyllum nodosum is a large, common cold water seaweed or brown alga (Phaeophyceae) in the family Fucaceae. Its common names include knotted wrack, egg wrack, feamainn bhuí, rockweed, knotted kelp and Norwegian kelp. It grows only in the northern Atlantic Ocean, along the north-western coast of Europe including east Greenland and the north-eastern coast of North America. Its range further south of these latitudes is limited by warmer ocean waters. It dominates the intertidal zone. Ascophyllum nodosum has been used numerous times in scientific research and has even been found to benefit humans through consumption.
Caulerpa racemosa is a species of edible green alga, a seaweed in the family Caulerpaceae. It is commonly known as sea grapes and is found in many areas of shallow sea around the world. Despite the name, it is not related to grapes. There are a number of different forms and varieties, and one that appeared in the Mediterranean Sea in 1990, which is giving cause for concern as an invasive species.
Elysia subornata is a species of small sea slug, a marine opisthobranch gastropod mollusk in the family Plakobranchidae.
Oxynoe olivacea is a species of small green bubble snail or sea slug, a marine gastropod mollusk in the family Oxynoidae.
Caulerpa lentillifera or sea grape is a species of ulvophyte green algae from coastal regions in the Asia-Pacific. This seaweed is one of the favored species of edible Caulerpa due to its soft and succulent texture. It is traditionally eaten in the cuisines of Southeast Asia, Oceania, and East Asia. It was first commercially cultivated in the Philippines in the 1950s, followed by Japan in 1968. Both countries remain the top consumers of C. lentillifera. Its cultivation has since spread to other countries, including Vietnam, Taiwan, and China. C. lentillifera, along with C. racemosa, are also known as sea grapes or green caviar in English.
Asparagopsis armata is a species of marine red algae, in the family Bonnemaisoniaceae. English name(s) include red harpoon weed. They are multicellular eukaryotic organisms. This species was first described in 1855 by Harvey, an Irish botanist who found the algae on the Western Australian coast. A. armata usually develops on infralittoral rocky bottoms around the seawater surface to around 40m of depth. Marine algae like A. armata are considered "autogenic ecosystem engineers" as they are at the very bottom of the food chain and control resource availability to other organisms in the ecosystem.
Penicillus capitatus is a species of macroalgae, seaweed, that is part of the Udoteaceae, a larger family of algae. The P. Capitatus is a member of green macroalgae, Chlorophyta, so they share some similarities to their terrestrial counterparts. Due to their distinct shape, the Penicillus genus can be referred to as Brush Seaweed, Shaving Brush, or the Mermaid's Shaving Brush.
The salema porgy, also known as the dreamfish, salema, cow bream, karanteen, salpa, saupe, strepie or goldline, is a species of marine ray-finned fish belonging to the family Sparidae, which includes the seabreams and porgies. It is the only species in the monospecific genus Sarpa. It is found in the eastern Atlantic Ocean, Mediterranean Sea and southwestern Indian Ocean. This species has been known to cause ichthyoallyeinotoxism when eaten.
Edible seaweed, or sea vegetables, are seaweeds that can be eaten and used for culinary purposes. They typically contain high amounts of fiber. They may belong to one of several groups of multicellular algae: the red algae, green algae, and brown algae. Seaweeds are also harvested or cultivated for the extraction of polysaccharides such as alginate, agar and carrageenan, gelatinous substances collectively known as hydrocolloids or phycocolloids. Hydrocolloids have attained commercial significance, especially in food production as food additives. The food industry exploits the gelling, water-retention, emulsifying and other physical properties of these hydrocolloids.
Sargassum muticum, commonly known as Japanese wireweed or japweed, is a large brown seaweed of the genus Sargassum. It is an invasive seaweed with high growth rate. It has an efficient dispersion thanks to its floats.
Cymodocea nodosa is a species of seagrass in the family Cymodoceaceae and is sometimes known as little Neptune grass. As a seagrass, it is restricted to growing underwater and is found in shallow parts of the Mediterranean Sea and certain adjoining areas of the Atlantic Ocean.
Caulerpa prolifera is a species of green alga, a seaweed in the family Caulerpaceae. It is the type species of the genus Caulerpa, the type location being Alexandria, Egypt. It grows rapidly and forms a dense mass of vegetation on shallow sandy areas of the sea.
Caulerpa cylindracea is a species of seaweed in the Caulerpaceae family.
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