Monostichella Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 125(1-2): 95 (1916)
= Cryptocline Petr., Annls mycol. 22(3/6): 402 (1924)
Facesoffungi number: FoF 07452
Ascomycota, genera incertae sedis
Saprobic on the host plant. Sexual morph: undetermined. Asexual morph: Conidiomata acervular, scattered to gregarious or confluent, subepidermal to epidermal, immersed, usually circular, unilocular, glabrous. Ostiole absent, dehiscence by irregular splits of overlying host tissue. Conidiomatal wall composed of thin-walled, pale brown to hyaline cells of textura angularis in the basal part. Conidiophores usually reduced to conidiogenous cells. Conidiogenous cells arising from the inner layer cells of the basal stroma, hyaline, enteroblastic, phialidic, lageniform to cylindrical, discrete, determinate, smooth-walled. Conidia hyaline, ovoid, ellipsoidal or somewhat pyriform, with truncate base and obtuse apex, unicellular, smooth-walled (Sutton 1980, Morgan-Jones et al. 1972a).
Type species: Monostichella robergei (Desm.) Höhn., Sber. Akad. Wiss. Wien, Math.-naturw. Kl., Abt. 1 125(1-2): 95 (1916)
Notes: Monostichella was re-described and re-illustrated by Sutton (1980) and Morgan-Jones et al. (1972a). Conidia ranging in shape from ellipsoid to pyriform in Monostichella invite comparison with Cryptocline, Erythrogloeum, and Gloeosporidina (Sutton 1980). However, Erythrogloeum possesses eustromatic, pycnidial conidiomata, which distinguish it from the acervular conidiomata in Cryptocline, Gloeosporidina and Monostichella. Gloeosporidina has hyaline to pale brown, cylindrical to subcylindrical, branched conidiophores, which are usually reduced to conidiogenous cells in Cryptocline and Monostichella. Cryptocline has been distinguished from Monostichella by its flared conidiogenous cells, but this minor difference cannot be used to separate these two genera. Therefore, we synonymise Cryptocline with Monostichella, because the latter name has priority. Erythrogloeum and Gloeosporidina were placed in Diaporthales based on molecular data (Crous et al. 2012, Senanayake et al. 2018), and we speculate that Monostichella might be related to Diaporthales. Wijayawardene et al. (2017b) estimated 15 taxa in the genus. Further studied with fresh collections and cultures are needed.
Distribution: Austria, Canada, Czechoslovakia, Hungary, India, Iraq, Italy, Germany, Romania, USA (Sutton 1980).
Monostichella robergei (redrawn from Morgan-Jones et al. 1972a) a Conidia. b Vertical section of conidioma. c Conidiogenous cells and developing conidia.
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.