Dr. K. Chandrasekharan can be contacted at E-mail: email@example.com
|Taken from: http://www.palaeos.com/Eukarya/Units/Microsporidia/Microsporidia.000.html|
The microsporidia have occupied the attention of taxonomists for a long time and have been subject to several reclassifications at all levels of organisation, from the species level up to that of their phylum’s affinity with other eukaryotes. The classification of Microsporidia has evolved through time with growing scientific research and the specifics are still thoroughly debated. Recent studies indicate phylum Microspora under the Fungal kingdom or at least as a sister kingdom to Fungi. The class, order and family within the Microspora phylum are also frequently revised and debated. Since from its inception, microsporidia was changed to distinct and varied taxonomic groups and hence microsporidian group can be considered as a taxonomic nomad.The name "Protozoa" was coined by Goldfuss (1817) and Siebold (1845) defined it and made phylum Protozoa. Order Microsporidia was erected by Balbiani in 1882 and initially this order was placed under the phylum Protozoa (kingdom Protista), and class Sporozoa along with the well known pathogens like Plasmodium and Leishmania. Later Doflein (1901) created a subclass Cnidosporidia, and order Microsporidia came under this sub class until a separate class Microsporidea under the sub phylum Cnidospora was erected by Honigberg et al. (1964)
Classification of microsporidia as a class in the phylum Protozoa (Honigberg et al. ,1)964)
Microsporidia was later elevated into a separate phylum called Microspora under sub kingdom Protozoa which was erected in 1969 to accommodate this unique group of organisms (Sprague (1969, 1977), Levine et al. (1980)).
Classification of Microspora as a separate phylum of the animal subkingdom Protozoa (Levine et al. 1980, Sprague 1969, 1977)
Sprague et al. (1992) introduce a different classification system, based on whether the species is diplokaryotic at some point in the life cycle (Dihaplophasea) or uninucleate throughout its life cycle (Haplophasea). The Dihaplophasea are further separated into those in which the diplokaryon is formed through meiosis (Meiodihaplophasida) and those in which the diplokaryon is formed through nuclear dissociation (Dissociodihaplophasida).
Taxonomic position of Nosema sp. in the Phylum Microsporidia (Sprague et al.1992)
Balbiani G. (1882) Sur les microsporidies ou psorospermies des articules. C. R. Acad. Sci. 95: 1168–1171.