Glomerales

Glomerales is an order of symbiotic fungi within the phylum Glomeromycota.

Glomerales Temporal range: 460–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Glomus mosseae
Scientific classification
Domain:	Eukaryota
Kingdom:	Fungi
Division:	Glomeromycota
Class:	Glomeromycetes
Order:	Glomerales Morton & Benny, 1990[1]
Families and genera
Glomeraceae Funneliformis Funneliformis caledonius Funneliformis coronatus Funneliformis mosseae Glomus Glomus cerebriforme Glomus macrocarpum Palaeoglomus↑ Palaeoglomus boullardi↑ Palaeoglomus grayi† Palaeoglomus strotheri† Rhizophagus Rhizophagus clarus Rhizophagus intraradices Rhizophagus irregularis Rhizophagus proliferus Sclerocystis Septoglomus Septoglomus constrictum Claroideoglomeraceae Claroideoglomus Claroideoglomus claroideum Claroideoglomus drummondii Claroideoglomus etunicatum Claroideoglomus luteum Claroideoglomus walkeri
Synonyms
Glomales

Biology

These fungi are all biotrophic mutualists. Most employ the arbuscular mycorrhizal method of nutrient exchange with plants. They produce large (.1-.5mm) spores (azygospores and chlamydospores) with thousands of nuclei.^[2]

Phylogeny

All members of their phylum were once thought to be related to the Endogonaceae, but have been found through molecular sequencing data, to be a closer relation to the Dikarya.^[3] Their fossil record extends back to the Ordovician period (460 million years ago).^[2]

Meiosis

Glomerales fungi were thought to have reproduced clonally for several hundred million years and are therefore an ancient asexual lineage.^[4] However, homologs of 51 meiotic genes, including seven genes specific for meiosis, were found to be conserved in the genomes of four Glomus species.^[4] Thus it now appears that these supposedly ancient asexual fungi may be capable of meiosis and perhaps also of a cryptic sexual or parasexual cycle.^[4]

Orthography

The family name Glomeraceae upon which this order level name is based, was incorrectly spelled 'Glomaceae', hence the order name was incorrectly spelled 'Glomales'. Both are correctable errors, to Glomeraceae and Glomerales, as governed by the International Code of Botanical Nomenclature. The incorrect spellings are commonplace in the literature.

See also

• Glomalin

References

1. J.B. Morton (1990). "Revised classification of the arbuscular mycorrhizal fungi (Zycomycetes): a new order, Glomales, two new families, Acaulosporaceae and Gigasporaceae, with an emendation of Glomaceae". Mycotaxon. 37: 473.
2. C.J. Alexopolous, C.W. Mims & M. Blackwell (2004). Introductory Mycology (4th ed.). Hoboken NJ: John Wiley and Sons. ISBN 0-471-52229-5.
3. A. Schüßler; et al. (December 2001). "A new fungal phylum, the Glomeromycota: phylogeny and evolution". Mycol. Res. 105 (12): 1413–1421. doi:10.1017/S0953756201005196.
4. Sébastien Halary, Shehre-Banoo Malik, Levannia Lildhar, Claudio H. Slamovits, Mohamed Hijri, Nicolas Corradi, Conserved Meiotic Machinery in Glomus spp., a Putatively Ancient Asexual Fungal Lineage, Genome Biology and Evolution, Volume 3, 2011, Pages 950–958, https://doi.org/10.1093/gbe/evr089