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Related to Microsporidia: cryptosporidium, Enterocytozoon bieneusi



an order of protozoans of the class Cnidosporidia. There are more than 20 genera, comprising more than 300 species. They are intracellular parasites of animals, predominantly arthropods and fish. Microsporidian amoeboids reproduce asexually (by simple division and schizogony) in the cell cytoplasm of the animal host. After the sexual process (autogamy), formation of spores (sporogony) begins. The spores are usually oval (2–10 microns in length) and have a spirally wound polar thread that serves to embed the parasite in the tissue of a new host.

Microsporidians cause diseases, microsporidioses, in various animals. For example, microsporidians of the genus Nosema are the causative agents of nosematoses, and Nosema cuniculi is possibly the cause of the human disease multiple sclerosis. Many species of Microsporidia are parasites of fish and commercial arthropods. More than 100 species are beneficial as parasites of harmful arthropods, since they cause their mass destruction; the possibility of using these species for the biological control of pests is being investigated.


Zhiznzhivotnykh, vol. 1. Moscow, 1968.
Weiser, J. Die Mikrosporidien als Parasiten der Insekten. Hamburg-Berlin, 1961. I. V. Issi
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Examining a handful of genes, Keeling and other researchers demonstrated that the single-gene tree had put microsporidia in the wrong kingdom.
Modified trichrome stain (Hi-media laboratories, India, Qualigens Fine Chemicals, India) was used for detecting Microsporidia (20).
Currently, microsporidia have been reported only in oysters, mussels, and cockles from Europe, Australia, California, and the eastern United States (Figueras et al.
Now, CMAVE and SABCL scientists are looking to add a new scientific wrinkle--using the phorid fly as a vector for infecting the fire ant population with the microsporidia.
The newly recognized relationship between mitochondria and hydrogenosomes, as well as the research on microsporidia and diplomonads, pushes the origin of these two organelles back to the earliest eukaryotes, if not earlier.
Microsporidia is a phylum of eukaryotes that contains almost 160 genera (1).
The research team determined that the microsporidia were decreasing weevil survival rates by 30 percent and reducing reproductive capacity by 72 percent in one weevil species and 62 percent in the other.
1-3] Microsporidia are obligate intracellular parasites that lack mitochondria and use a unique polar tube apparatus to infect the host cell.
New entries include Cryptosporium parvum and various species of Microsporidia implicated in human disease.
Because microsporidia attack, weaken and sometimes kill the larvae, which are currently treated with chemicals, scientists hope to use them to control the borers.