Bivalvulida is an order of

myxosporea Myxosporea is a class of microscopic parasites, belonging to the Myxozoa clade within Cnidaria. They have a complex life cycle which comprises vegetative forms in two hosts, an aquatic invertebrate (generally an annelid but sometimes a bryozoan) ...

n parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as '' Myxobolus cerebralis'' and ''

Ceratomyxa shasta ''Ceratonova shasta'' (syn. ''Ceratomyxa shasta'') is a myxosporean parasite that infects salmonid fish on the Pacific coast of North America. It was first observed at the Crystal Lake Hatchery, Shasta County, California, and has now been reporte ...

''. The Myxosporean stages of members of the bivalvulida are characterised by their two spore valves (hence the name), which meet in a "suture line" which encircles the spore. They usually contain two

polar capsule Polar capsules are structures found in the valves of Myxosporean parasites, which contain the polar filament. The polar capsule is constructed of a proteinaceous and a polysaccharide layer, both layers of which continue into the polar filament. ...

s, but species have been reported which contain either one or four.

Taxonomy and systematics

The order Bivalvulida is composed of three suborders and thirteen families. *Suborder Platysporina Kudo, 1919Kudo, R. (1919). Studies on Myxosporidia. A synopsis of genera and species of Myxosporidia. ''Illinois Biological Monographs'', 5. **

Myxobolidae Myxobolidae is a Family (biology), family of myxosporean parasites which typically infect freshwater fishes, and includes the economically significant species, ''Myxobolus cerebralis''. They have been shown to have a complex life cycle, involving ...

Thélohan, 1892Thélohan, P. (1892). Observation sur les myxosporidies et essai de classification de ces organismes. ''Bulletin de la Société Philomatique de Paris'', 4, 165–178. *Suborder Sphaeromyxina Lom & Noble, 1984Lom, J. & Noble, E. R. (1984). Revised classification of the class Myxosporea Bütschli, 1881. ''Folia Parasitologica'', 31, 193–205. ** Sphaeromyxidae Lom & Noble, 1984 *Suborder Variisporina Lom & Noble, 1984 ** Auerbachiidae ** Alatasporidae Shulman, Kovaleva & Dubina, 1979Shulman, S. S., Kovaleva, A. A. & Dubina, V. R. (1979). New myxosporidians from fishes of the Atlantic coast of Africa. ''Parazitologiya'', 13, 71–79. **

Ceratomyxidae Ceratomyxidae is a family of myxozoa Myxozoa (etymology: Greek: μύξα ''myxa'' "slime" or "mucus" + thematic vowel o + ζῷον ''zoon'' "animal") is a subphylum of aquatic cnidarian animals – all obligate parasites. It contains the smal ...

Doflein, 1899Doflein, F. (1899). Amerikanische Dekapoden der k. bayerischen Staatssammlungen. ''Sitzungberichte der mathematisch-physische Klasse der bayerischen Akademie der Wissenschaften'', 29, 177–195. **

Chloromyxidae ''Chloromyxum'' is a genus of parasitic, myxosporean cnidarians belonging to the family Chloromyxidae. The species of this genus are found in Northern America and Australia. Species: *''Chloromyxum argusi'' *'' Chloromyxum atlantoraji'' *''C ...

Thélohan, 1892 **

Coccomyxidae Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as ''Myxobolus cerebralis'' and ''Ceratomyxa shasta''. The Myxosporean stages of me ...

Léger & Hesse, 1907Léger, L. & Hesse, E. (1907). Sur une nouvelle Myxosporidie parasite de la sardine. ''Compte Rendus de l'Académie des Sciences, Paris'', 145, 85–87. **

Fabesporidae Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as '' Myxobolus cerebralis'' and ''Ceratomyxa shasta''. The Myxosporean stages of m ...

Naidenova & Zaika, 1969Naidenova, N. N. & Zaika, W. E. (1969). Two new species of Protozoa from the fishes of the Black Sea. ''Parazitologiya'', 3, 97–101. ** Myxidiidae Thélohan, 1892 **

Myxobilatidae Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as '' Myxobolus cerebralis'' and ''Ceratomyxa shasta''. The Myxosporean stages of m ...

Shulman, 1953Shulman, S. S. (1953). New and little-studied myxosporids. ''Zoologicheskii Zhurnal'', 32(3), 384–393. ** Ortholineidae Lom & Noble, 1984 ** Parvicapsulidae Shulman, 1953 **

Sinuolineidae Bivalvulida is an order of myxosporean parasites which contains a number of species which cause economically significant losses to aquaculture and fisheries, such as '' Myxobolus cerebralis'' and ''Ceratomyxa shasta''. The Myxosporean stages of m ...

Shulman, 1959Shulman, S. S. (1959). New classification of Myxosporidia. ''Trudy Karel'skogo Filiala Akademii Nauk SSSR, Parazitologiya'', 33–47. ** Sphaerosporidae Davis, 1917Davis, H. S. (1917). The Myxosporidia of the Beaufort Region. A systematic and biologic study. ''Bulletin of the United States Bureau of Fisheries'', 35, 201–243.

Gallery

Drawings and scanning electron microscopy of species of ''

Chloromyxum ''Chloromyxum'' is a genus of parasitic, myxosporean cnidarians belonging to the family Chloromyxidae. The species of this genus are found in Northern America and Australia. Species: *''Chloromyxum argusi'' *'' Chloromyxum atlantoraji'' *''C ...

'' Parasite180057-fig1 Chloromyxum atlantoraji SEM.png, ''

Chloromyxum atlantoraji ''Chloromyxum'' is a genus of parasitic, myxosporean cnidarians belonging to the family Chloromyxidae. The species of this genus are found in Northern America and Australia. Species: *''Chloromyxum argusi'' *'' Chloromyxum atlantoraji'' *''C ...

'' Parasite180057-fig2 Chloromyxum atlantoraji drawing.png, ''

'' Parasite180057-fig4 Chloromyxum zearaji drawing.png, '' Chloromyxum zearaji ''

References

Myxosporea Cnidarian orders {{parasitic animal-stub