Cirsosia G. Arnaud, Annals d'École National d'Agric. de Montpellier, Série 2 16(1-4): 127 (1918) .
Index Fungorum number: IF 1065; Facesoffungi number: FoF 06734, 15 morphological species (Species Fungorum 2022), molecular data unavailable.
Epiphytes on leaves. Superficial hyphae with intercalary appressoria. Sexual morph: Thyriothecia solitary, gregarious, superficial, oval, ellipsoidal, X- or Y-shaped, easily removed from the host surface, black, opening by a linear fissure, with basal peridium poorly developed. Upper wall comprising linear, dark cells, which are branched at the margin. Hamathecium lacking pseudoparaphyses. Asci 8- spored, bitunicate, fissitunicate dehiscence not observed, globose to subglobose, apical region of asci usually with a thick opaque region, ocular chamber not observed, not staining blue in IKI. Ascospores overlapping, oblong to obvoid, hyaline when immature, brown when mature, 1- septate, echinate. Asexual morph: “Homalopeltis”, coelomycetous, conidiomata pycnidial, numerous, superficial, developing below the superficial hyphae, circular, dimidiate, fringed, brown to dark-brown, with a central ostiole. Conidiogenous cells monoblastic. Conidia 1–2- celled, elongate ellipsoidal, upper end rounded or acuminate, lower end with truncate hilum, septum central or in upper third, hyaline, becoming brown (Adapted from Hongsanan et al. 2014).
Type species: Cirsosia manaosensis (Henn.) G. Arnaud
Notes: Cirsosia was introduced by Arnaud (1917) with C. manaosensis as type species. Cirsosia is characterized by solitary, gregarious, superficial, oval, ellipsoidal thyriothecia, globose to subglobose asci and oblong to obvoid, hyaline, brown ascospores. The asexual morph is characterised by pycnidial, superficial conidiomata, monoblastic conidiogenous cells and 1–2- celled, elongate ellipsoidal conidia. Cirsosia is currently a distinct genus in Asterinaceae. Molecular data is lacking. Fresh collections and DNA sequence data are needed to confirm the taxonomic placement of the genus.