Ceratocystis Ellis & Halst., New Jersey Agric. Coll. Exp. Sta. Bull. 76: 14 (1890)
Hypocreomycetidae, Microascales, Ceratocystidaceae, Ceratocystis
Saprobic or pathogenic on stems or roots of vascular plants, some species associated with bark beetles. Sexual morph: Ascomata dark brown to black, solitary to aggregated, superficial or immersed in substrate, globose to subglobose, with ornamented or unornamented hyphae, with or without spines, spines if present dark brown to black. Ostiole dark-brown to black, hyaline at apex, with long necks, cylindrical, tapering to the apex, straight, ostiolar hyphae divergent, aseptate, tapering at the apex, hyaline to light brown. Peridium thin–walled, comprising pseudoparenchymatous cells of textura angularis in surface view. Asci dehiscent. Ascospores hyaline, 1-celled, variable in shape, fusoid, oblong, obovoid, cylindrical, or hat–shaped, curved, lunate, with or without a gelatinous sheath, accumulating in cream-coloured masses at apices of the ascomatal necks. Asexual morph: Conidiophores simple, tubular, flask shaped, narrowing at the apex, with phialidic conidiogenesis. Primary conidiophores phialidic, flask-shaped. Secondary conidiophores flaring or wide-mouthed. Primary conidia cylindrical, hyaline. Secondary conidia barrel-shaped to subglobose, hyaline to light brown. Aleurioconidia pale-brown to brown, globose, ovoid to pyriform, single or in chains (adapted from Maharachchikumbura et al. 2016).
Type species: Ceratocystis fimbriata Ellis & Halst., Bull. New York Agricultural Experimental Station 76: 14 (1890)
Notes: Ceratocystis is characterized by black, globose ascomatal bases with filiform, elongated necks terminating in an ostiole and sticky, hat-shaped ascospores (Upadhyay 1981, Seifert et al. 1993, de Beer et al. 2014). The asexual morph of most Ceratocystis species is chalara- or thielaviopsis-like and characterized by phialidic conidiogenous cells producing chains of hyaline, single-celled, cylindrical conidia called endoconidia, and in some cases secondary dark, barrel-shaped, thick-walled aleurioconidia which are commonly produced that facilitate survival in wood or soil during dry seasons (Hedgcock 1906, Harrington 2013, de Beer et al. 2014, Maharachchikumbura et al. 2016).
The history of Ceratocystis was discussed in Réblová et al. (2011), de Beer et al. (2014), Maharachchikumbura et al. (2016) and Holland et al. (2019). Ceratocystis species are important plant pathogens and act as causal agents of sap stain in timber and symbiotic associates of insects. For example, C. platani is an invasive alien pathogen of Platanus trees in Europe (Ocasio- Moraleset al. 2007), whereas C. albifundus is a virulent pathogen of Acacia mearnsii in Africa (Roux & Wingfield 2013). The ITS, tub1, tef1, rpb2, ms204 gene regions are used to identify species boundaries in Ceratocystis (Marin-Felix et al. 2017, Barnes et al. 2018). The loci rpb2 and ms204 provide stronger resolution among species than tef1 and tub1, but also need to be used in combination with ITS (Fourie et al. 2015).
Species illustrated in this entry:
Ceratocystis fimbriata Ellis & Halst.
Barnes I, Fourie A, Wingfield MJ, Harrington TC et al. 2018 – New Ceratocystis species associated with rapid death of Metrosideros polymorpha in Hawaii. Persoonia 40, 154–181
de Beer ZW, Duong TA, Barnes I, Wingfield BD, Wingfield MJ. 2014 – Redefining Ceratocystis and allied genera. Study in Mycology 79, 187–219
Fourie A, Wingfield MJ, Wingfield BD, Barnes I. 2015 – Molecular markers delimit cryptic species in Ceratocystis sensu stricto. Mycological Progress 14, 1–18
Harrington TC. 2013 – Ceratocystis diseases. Gonthier P, Nicolotti G (eds). Infectious Forest Diseases 230–255
Hedgcock GG. 1906 – Studies upon some chromogenic fungi which discolor wood. Missouri Botanical Garden Annual Report 17, 59–124
Holland LA, Lawrence DP, Nouri MT, Travadon R et al. 2019 – Taxonomic Revision and Multilocus Phylogeny of the North American Clade Of Ceratocystis. Fungal Systematics and Evolution 3, 135–156
Maharachchikumbura SSN, Hyde KD, Jones EBG, McKenzie EHC et al. 2016b – Families of Sordariomycetes. Fungal Diversity 79, 1–317
Marin-Felix Y, Groenewald JZ, Cai L, Chen Q et al. 2017 – Genera of phytopathogenic fungi: GOPHY 1. Study in Mycology 86, 99–216
Ocasio-Morales RG, Tsopelas P, Harrington TC. 2007 – Origin of Ceratocystis platani on native Platanus orientalis in Greece and its impact on natural forests. Plant Disease 91, 901–904
Réblová M. 2011 – New insights into the systematics and phylogeny of the genus Jattaea and similar fungi of the Calosphaeriales. Fungal Diversity 49, 167‒198
Roux J, Wingfield MJ. 2013 – Ceratocystis species on the African continent, with particular reference to C. albifundus, an African species in the C. fimbriata sensu lato species complex. The Ophiostomatoid Fungi: Expanding Frontiers. Biodiversity Series 12, 131–138
Seifert KA, Okada G. 1993 – Graphium anamorphs of Ophiostoma species and similar anamorphs of other ascomycetes. In: Wingfield MJ, Seifert KA, Webber JF (Eds). Ceratocystis and
Ophiostoma taxonomy, ecology, and pathogenicity. The American Phytopathological Society Press, St. Paul, Minnesota 27–41
Upadhyay HP. 1981 – A monograph of Ceratocystis and Ceratocystiopsis. The University of Georgia Press, Athens, Georgia