Camarosporiaceae Wanas., Wijayaw., K.D. Hyde & Crous, fam. nov. MycoBank MB821938.

Synonym: Camarosporiaceae Locq., Mycol. gén. struct. (Paris): 210 (1984); nom. inval., Art. 39.1 (Melbourne).

Saprobic, endophytic, pathogenic on leaves and wood in terrestrial habitats. Asexual morph: Conidiomata dimorphic, pycnidial, subcorticolous, single to gregarious, partly caespitose, globose, ostiole central, terete, short papillate. Conidiomata wall few-layered, consisting of a textura globulosa-angularis with red brown, thick-walled, and smooth cells. Conidiogenous cells formed from the inner cells of the pycnidial wall, doliiform, hyaline, thin-walled, annellidic. Conidia multicelled, muriformly septate, with one longitudinal or diagonal septum per cell and 1–2 per conidium, ellipsoidal, pyroid, clavate, straight to slightly curved, yellowish not brown, basal cell often paler or hyaline, wall golden. Synasexual morph: conidiomata separate, pycnidial, immersed to superficial, brown, globose, with 1–2 papillate ostioles, exuding a crystalline conidial mass. Conidiophores reduced to conidiogenous cells. Conidiogenous cells lining the inner cavity, hyaline, smooth, ampulliform. Conidia solitary, hyaline, smooth, subcylindrical, straight, rarely curved, apex obtuse, base truncate. Sexual morph: Ascomata gregarious to solitary, immersed to erumpent, globose to subglobose, black, unilocular, ostiolate. Ostiole black, papillate. Peridium with several cell layers of textura angularis, with outer layer brown to reddish brown, inner layer hyaline to sub hyaline. Asci stipitate, cylindrical, bitunicate, (2-)4–8-spored. Ascospores uniseriate, ellipsoidal, medium brown, mostly with obtuse ends, muriform, 3–8 transverse septa, with 1–2 longitudinal septa, constricted at septa.

Type genus: Camarosporium Schulzer.

Notes: To better resolve interfamilial/intergeneric level relationships and improve taxonomic issues within Pleosporineae, we validate Camarosporiaceae (Camarosporiaceae Locq. 1984 was not validly published, Art. 39.1) to accommodate Camarosporium and Camarosporomyces. Wijayawardene et al. (2014a) also proposed Camarosporiaceae to accommodate Camarosporium s. str. but it was not formerly introduced.

Camarosporium Schulzer, Verh. K.K. Zool.-Bot. Ges. Wien 17: 717. 1867.

Description and illustration: Crous & Groenewald (2017).

Type species: Camarosporium quaternatum (Hazsl.) Schulzer.

Notes: Camarosporium morphologically resembles genera such as Camarographium, Camarosporiopsis, Camarosporula, Dichomera, Didymellocamarosporium, Hazslinszkyomyces, Libertasomyces, Magnicamarosporium, Melanocamarosporium, Melnikia, Murilentithecium, Neocamarosporium, Paracamarosporium, Phragmocamarosporium, Pseudocamarosporium, Pseudohendersonia, Suttonomyces and Xenocamarosporium in conidial shape and septation. However, these taxa are phylogenetically distinct and have subtle but specific morphological differences (Sutton 1980, Butin 1993, Crous et al. 2011, 2013, 2014b, 2015, Wijayawardene et al. 2014a, 2014b, 2014c, 2015, 2016, Tanaka et al. 2015, Tian et al. 2015, Crous & Groenewald 2017).

Camarosporium quaternatum was introduced by Schulzer (1870) as the type species of Camarosporium. Schulzer (1870) did not provide any illustrations for Camarosporium quaternatum in his article and mentioned it is completely similar to Clinterium lycii, described in Hazslinszky (1865). The microfungal collections of F.A. Hazslinszky von Hazslin are preserved in the Hungarian Natural History Museum (BP), but the type of Cm. quaternatum has been lost. Therefore, in a recent study Crous & Groenewald (2017) designated the original illustrations as lectotypes, to facilitate epitypification.

Camarosporomyces Crous, IMA Fungus 8: 141. 2017.

Description and illustration: Crous & Groenewald (2017).

Type species: Camarosporomyces flavigenus (Constant. & Aa) Crous.

Notes: Camarosporomyces was introduced by Crous & Groenewald (2017) to accommodate Camarosporomyces flavigenus, a phoma-like fungus which was originally described as Phoma flavigena. In our molecular analyses, Camarosporomyces flavigenus is basal to other strains of Camarosporium quaternatum strains with good statistical support (Clade C in Fig).