Fungalpedia – Note 455, Ocellomma

 

Ocellomma Ertz & Tehler

Citation when using this data: Tibpromma et al. 2024 (in prep.) – Fungalpedia, Lichenicolous fungi.

Index FungorumFacesoffungi, MycoBankGenBank, Fig. 1 

Classification: Roccellaceae, Arthoniales, Arthoniomycetidae, Arthoniomycetes, Pezizomycotina, Ascomycota, Fungi.

Based on phylogeny of combined LSU and RPB2 sequences, Ocellomma formed a separate lineage from Diromma and Schismatomma (in Roccellaceae) (Ertz et al. 2014). Ertz et al. (2014) introduced Ocellomma as a distinct genus within Roccellaceae and typified by O. picconianum, this species had initially been described as Lecania picconiana by Baglietto (1862). Ocellomma comprises only two species: O. picconianum and O. rediuntum (Ertz et al. 2015Kantvilas et al. 2020). Members of Ocellomma are isolated from different hosts with sexual and asexual morphs, and they are mainly distributed in Italy and Southern California as lichens (Tehler 1993Ertz et al. 2014Kantvilas et al. 2020). Ocellomma sexual morph is characterized by thallus crustose ecorticate. Photobiont trentepohlioid. Ascomata erumpent and scattered, containing calcium oxalate, with hyaline to brown hypothecium, K+ olive and KI+ violet, branched paraphysoids, myrticola-type asci containing 8-spored with hyaline and fusiform ascospores, 3-septate and without a gelatinous sheath (Ertz et al. 2014Kantvilas et al. 2020). The asexual morph is characterized by numerous pycnidia, visible as black, semi-immersed, bacilliform conidia, straight or curved (Ertz et al. 2014Kantvilas et al. 2020).

Type species: Ocellomma picconianum (Bagl.) Ertz & Tehler 

Other accepted species: Species Fungorum – search Ocellomma

 

 

Figure 1 – Morphology of Ocellomma. a, b Appearance of ascomata on substrates with whitish margins. c Ascus. d Ascospores and conidia. Scale bars: b = 1 mm, c, d = 10 μm. Redrawn from Ertz et al. (2014) and Kantvilas et al. (2020).

 

References 

Ertz D, Tehler A, Irestedt M, Frisch A. et al. 2014 – A large-scale phylogenetic revision of Roccellaceae (Arthoniales) reveals eight new genera. Fungal Diversity 70, 31–53.

Kantvilas G, Gueidan C, Tehler A. 2020 – The strange case of Ocellomma rediuntum (Arthoniales: Roccellaceae) in Australia: a remarkably disjunct lichen. The Lichenologist 52(3), 187–195.

Tehler A. 1993 – The genus Schismatomma (Arthoniales, Euascomycetidae). Opera Botanica 118, 1–38.

 

Entry by

Lu L, Center for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, Yunnan 655011, China; Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand; School of Science, Mae Fah Luang University, Chiang Rai 57100, Thailand.

 

(Edited by Saowaluck Tibpromma, Samaneh Chaharmiri-Dokhaharani, & Achala R. Rathnayaka)

 

Published online 29 November 2024