Glomerellaceae Locq., Mycologia 98(6): 1083 (2007)
Index Fungorum number: IF80186; Facesoffungi number: FoF01100; 894 species.
Parasitic, endophytic and saprobic on plant leaves, stems and fruits. Sexual morph: Ascomata solitary or gregarious, globose to subglobose, dark brown to black, ostiole periphysate. Peridium composed of pale to medium brown flattened cells of textura angularis. Paraphyses composed of hyaline, septate, branched at the base, rounded at the apex. Asci 8-spored, unitunicate, cylindrical to subfusoid, short pedicellate, with a J-, refractive ring at the apex, Ascospores uni- to biseriate, hyaline, aseptate, smooth-walled, cylindrical, oval, fusiform or rhomboid, straight or curved, one end ± acute and one end rounded or both ends rounded. Asexual morph: Coelomycetous. Conidiomata acervular, ranging from sporodochia-like aggregations to closed conidiomata that open by rupture, conidiophores and setae formed on cushions of pale to medium brown, roundish to angular cells. Setae may or may not be present, straight, pale to dark brown, sometimes hyaline towards the tip, smooth-walled, verruculose to verrucose, 1–8-septate, base cylindrical, conical or slightly inflated, tip ± rounded to ± acute. Conidiophores hyaline to pale brown, simple or septate, branched or unbranched, smooth-walled, sometimes verruculose. Conidiogenous cells enteroblastic, hyaline to pale brown, smooth-walled, discrete, ampulliform, cylindrical, doliiform or ellipsoidal, collarette usually distinct, periclinal thickening visible to conspicuous, sometimes extending to form new conidiogenous loci (percurrent) or surrounded by a gelatinous coating. Conidia hyaline, smooth-walled, aseptate, cylindrical, clavate, fusiform, sometimes ellipsoidal to ovoid, straight or curved, apex rounded to acute, sometimes with a filiform appendage, base rounded to truncate, sometimes with a prominent hilum. Appressoria single or in small groups, pale to dark brown, with a globose, elliptical, clavate, navicular or irregular outline and an entire, undulate or lobate edge (adapted from Maharachchikumbura et al. 2016b).
Type genus – Colletotrichum Corda
Notes – The ordinal name Glomerellales including Colletotrichum (= Glomerella) and three other genera in a non-ranked group “Eu-Glomérellales” was introduced by Chadefaud (1960), but was not validly published. Earlier classification placed Colletotrichum in Phyllachoraceae (Ainsworth 1971, Barr 1983, Hawksworth et al. 1983). However, due to its astromatic nature, it has long been considered to be an outlier within Phyllachoraceae (Cannon 1991). The family name Glomerellaceae was invalidly published by Locquin (1984) and was ignored until preliminary sequence-based studies and ontogenic research confirmed that Colletotrichum and Phyllachora did not belong to the same order (Uecker 1994). In the 9th edition of the Dictionary of Fungi the family name Glomerellaceae was adopted and placed with an uncertain position within the subclass Sordariomycetidae (Kirk et al. 2001). Zhang et al. (2006) validated Glomerellaceae with a Latin description, while placing it within Hypocreomycetidae. Kirk et al. (2008) placed this family as an uncertain position in the subclass Hypocreomycetidae. The phylogenetic position of Glomerellaceae was further clarified and validated by Réblová et al. (2011) in a study using ITS, LSU, SSU and rpb2 genes and two new families, Australiascaceae and Reticulascaceae, occupied a common clade with Glomerellaceae. Maharachchikumbura et al. (2016b) provided evidence for the phylogenetic position of Glomerellaceae within Glomerellales. This family is monotypic with the single genus Colletotrichum.
Ecological and economic significance of Glomerellaceae
Colletotrichum includes many plant pathogens of major importance causing diseases of a wide variety of plants (Cannon et al. 2012b, Jayawardena et al. 2016, Marin-Felix et al. 2017). Fruit production is especially affected.