Cornutispora Piroz., Mycologia 65(4): 763 (1973)
Ascomycota, genera incertae sedis
Fungicolous on apothecia of discomycetes. Sexual morph: undetermined. Asexual morph: Conidiomata black, stromatic, pycnidial, solitary to gregarious or often confluent, deeply immersed, then becoming partly erumpent through the outer layers of the excipulum, unilocular or multi-locular, ovoid to subglobose, glabrous, ostiolate. Ostiole single, cylindrical to irregular, centrally located. Conidiomatal wall composed of thick-walled, dark brown to black or hyaline cells of textura angularis to textura intricata. Conidiophores arising from the innermost wall layer of conidiomata, hyaline, branched, septate, smooth-walled. Conidiogenous cells hyaline, cylindrical, discrete or integrated, indeterminate. Conidia hyaline, conidium body subcylindrical to naviculate or narrow cuneiform, with a small attachment scar, straight or slightly curved, aseptate, bearing appendages at both ends and middle of the conidial body; apical appendages 1, 2 or 3, mostly divergent, sometimes single, unbranched, basal appendage single, mostly unbranched, occasionally divergent at middle part, eccentric.
Types species: Cornutispora limaciformis Piroz., Mycologia 65(4): 763 (1973)
Notes: The genus was introduced by Pirozynski (1973) based on C. limaciformis Piroz., which parasitized apothecia of Therrya fuckelii (Helotiales) on branches of Pinus resinosa (Pinaceae). Cornutispora is characterized by its fungicolous habitat and aseptate, staurospores or y-shaped conidia. Hawksworth (1976) added species, C. lichenicola from a thallus of Parmelia sulcata, which is distinguished by the much smaller conidia. Subsequently, Gierl and Kalb (1993) described C. ciliata Kalb, from apothecia of Dibaeis cretacea in Tasmania. Punithalingam (2003) re-examined the type materials of C. ciliata, C. lichenicola and C. limaciformis, and concluded that the size and shape of the conidia and the two apical bifurcations or segments can be used as criteria to distinquishish Cornutispora species. Cornutispora intermedia and C. pittii were introduced by Punithalingam (2003). Index Fungorum (2019) lists nine species, while Wijayawardene et al. (2017b) estimated there are five species.
We examined the holotype and isotype of Cornutispora limaciformis, of which the latter is not in good condition, and provide a detailed description and photoplates of the genus. Besides, we found that apical appendages or divergent arms vary, and cannot be used to distinguish species. Since, molecular data is lacking for the genus, the natural placement of Cornutispora is unclear.
Distribution: Australia, Brazil, Canada, Denmark, Estonia, France, Germany, Italy, Poland, Spain, Sweden, UK, USA (Nag Raj 1993, Punithalingam 2003, https://www.gbif.org/).
Li WJ, McKenZie EHC, Liu JK, Bhat DJ, Dai DQ, Caporesi E, Tian Q, Maharachcikumbura SSN, Luo ZL, Shang QJ, Zhang JF, Tangthirasunun N, Karunarathna SC, Xu JC, Hyde KD (2020) Taxonomy and phylogeny of hyaline-spored coelomycetes. Fungal Diversity 100: pages279–801.