Opisthosporidia

Opisthosporidia is a superphylum of intracellular parasites with amoeboid vegetative stage, defined as a common group of eukaryotic groups Microsporidia, Cryptomycota (also known as Rozellida, Rozellomycota, or Rozellosporidia) and Aphelidea.^[1] They have been considered to represent a monophyletic lineage with shared ecological and structural features, being a sister clade of the Fungi.^[1][2] Together with the Fungi they represent a sister clade of the Cristidiscoidea, together forming the Holomycota.

"Opisthosporidia"
Sporoblast of Fibrillanosema crangonycis (Microsporidian)
Scientific classification
Domain:	Eukaryota
Clade:	Amorphea
Clade:	Obazoa
(unranked):	Opisthokonta
Clade:	Holomycota
(unranked):	Zoosporia
(unranked):	Opisthosporidia Karpov et al., 2014[1]
Groups included
Aphelida Rozellida Microsporidia  ? BCG1  ? BCG2  ? GS01  ? Namako-37
Cladistically included but traditionally excluded taxa
Eumycota

Several other basal groups of the freshwater, marine and soil-inhabiting Holomycota were identified in recent studies, as the 'basal clone group 1' (BCG1=NCLC1), 'basal clone group 2' (BCG2), 'basal marine group' (NAMAKO-37), 'basal group GS01', the inner relationships of Opisthosporidia were clarified and their monophyly questioned: Cryptomycota and Microsporidia were proposed to join the phylum Rozellomycota, while Aphelidea were considered as a separate, though related phylum and all these groups were considered basal lineages of the kingdom Fungi.^[3][4][2][5]

Instead of probably paraphyletic Opisthosporidia, the phyla Rozellomycota and Aphelidiomycota (or monotypic subkingdoms Rozellomyceta and Aphelidiomyceta) are recently applied in some taxonomical systems of the kingdom Fungi for the basal lineages, and the other fungal lineages are grouped into a clade of True Fungi (Eumycota).^[6] However, the taking up of the name Rozellomycota in such a broad sense can be considered premature, especially as the structure and biological features of a larger part of these organisms are unclear as they are known only from environmental sequences. The borders between Fungi and Protista are therefore unstable and final delimitation of taxa is problematic due to poor coverage of molecular data for the representatives of the basal groups.^[6]

Opisthokonts	Holomycota Cristidiscoidea Fonticulida Nucleariida Fungi BCG2 + GS01 BCG1 Rozellomyceta Namako-37 Microsporidia Chytridiopsidea Metchnikovellea Opisthosporidia Microsporea Cryptomycota = Rozellosporidia Aphelidiomyceta Aphelida True Fungi Holozoa Ichthyosporea Pluriformea Corallochytrium Syssomonas Filozoa Filasterea Choanozoa Choanoflagellatea Animalia

References

1. Karpov, Sergey; Mamkaeva, Maria A.; Aleoshin, Vladimir; Nassonova, Elena; Lilje, Osu; Gleason, Frank H. (2014-01-01). "Morphology, phylogeny, and ecology of the aphelids (Aphelidea, Opisthokonta) and proposal for the new superphylum Opisthosporidia". Frontiers in Microbiology. 5: 112. doi:10.3389/fmicb.2014.00112. PMC 3975115. PMID 24734027.
2. Torruella, Guifre; Grau-Bove, Xavier; Moreira, David; Karpov, Sergey A.; Burns, John; Sebe-Pedros, Arnau; Volcker, Eckhard; Lopez-Garcia, Purificacion (2018-12-19). "Global transcriptome analysis of the aphelid Paraphelidium tribonemae supports the phagotrophic origin of fungi". Commun Biol (231). doi:10.1038/s42003-018-0235-z.
3. Tedersoo, Leho; Bahram, Mohammad; Puusepp, Rasmus; Nilsson, R.Henrik; James, Timothy Y. (2017). "Novel soil-inhabiting clades fill gaps in the fungal tree of life". Microbiome. 5 (42). doi:10.1186/s40168-017-0259-5. ISSN 2049-2618. PMC 5385062.
4. Tedersoo, Leho; Sánchez-Ramírez, Santiago; Kõljalg, Urmas; Bahram, Mohammad; Döring, Markus; Schigel, Dmitry; May, Tom; Ryberg, Martin; Abarenkov, Kessy (2018). "High-level classification of the Fungi and a tool for evolutionary ecological analyses". Fungal Diversity. 90 (1): 135–159. doi:10.1007/s13225-018-0401-0. ISSN 1560-2745.
5. Bass, David; Czech, Lucas; Williams, Bryony A. P.; Berney, Cédric; Dunthorn, Micah; Mahé, Frederic; Torruella, Guifré; Stentiford, Grant D.; Williams, Tom A. (2018-04-28). "Clarifying the Relationships between Microsporidia and Cryptomycota". Journal of Eukaryotic Microbiology. 65 (6): 773–782. doi:10.1111/jeu.12519. ISSN 1066-5234. PMC 6282948. PMID 29603494.
6. Wijayawardene, NN; Hyde, KD; Al-Ani, LKT; Tedersoo, L; Haelewaters, D; Rajeshkumar, KC; Zhao, RL (18 March 2020). "Outline of Fungi and fungus-like taxa". Mycosphere. 11 (1: 8): 1060–1456. doi:10.5943/mycosphere/11/1/8. hdl:10481/61998. ISSN 2077-7019.