Cyphellophora G.A. de Vries, Mycopath. Mycol. appl. 16(1):47(1962)

Cyphellophora is cosmopolitan, comprising species distributed from a broad range of environmental sources as human and animal disease, saprobes, epiphytes and plant pathogens (de Hoog et al. 1999, 2000; Jacob and Bhat 2000; Decock et al. 2003; Crous et al. 2007; Zhuang et al. 2010; Feng et al. 2014; Mayfield et al. 2012; Gao et al. 2015; Phookamsak et al. 2019). Most species, including the type species, C. laciniata, were isolated from nails or skin of humans, resulting in clinical symptoms (Feng et al. 2014). Phylogenetically, C. phyllostachysdis clustered with C. europaea, a human or mammal infection of hyperkeratosis (de Hoog et al. 2000). In contrast, C. phyllostachysdis causes sooty blotch and flyspeck (SBFS) of bamboo and is not found in humans (Gao et al. 2015). The sooty mold species C. jingdongensis was introduced with a sexual morph; it reduces plant photosynthesis but does not damage or cause disease of the plant (Chomnunti et al. 2014; Yang et al. 2018).

Classification – Eurotiomycetes, Chaetothyriomycetidae, Chaetothyriales, Cyphellophoraceae

Type species – Cyphellophora laciniata G.A. de Vries, Mycopath. Mycol. appl. 16(1):47(1962)

Distribution – Australia, Brazil, China, Germany, India, Israel, Korea, Taiwan

Disease symptoms – Sooty blotch and flyspeck (main symptoms of this disease are given under Chaetothyrina).

To date, C. artocarpi, C. guyanensis, C. jingdongensis, C. musae, C. olivacea, C. oxyspora, C. phyllostachydis and C. sessilis have been isolated from plant materials (Gams and Holubová-Jechová 1976; de Hoog et al. 1999; Decock et al. 2003; Gao et al. 2015; Yang et al. 2018). Cyphellophora artocarpi, C. musae, C. phyllostachydis and C. sessilis were reported to cause sooty blotch and flyspeck from apple, jackfruit (Artocarpus heterophyllus) and bamboo (Phyllostachys heterocycla, Sinobambusa tootsik), resulting in significant economic damage (Zhuang et al. 2010; Mayfield et al. 2012; Gao et al. 2015).

Hosts – Artocarpus heterophyllus, Dendrocalamus strictus, Eucalyptus sp., Helomeco velane, Hylomecon verlance, Malus domestica, Musa sp., Phyllostachys sp., Sinobasmbusa tootsik, and Stenocalyx uniflorus.

Morphological based identification and diversity

It is difficult to identify this black yeast-like genus based solely on morphological characters since the characters are very similar to those of other black yeast-like fungi, such as Phialophora and Pseudomicrodochium. Species of Cyphellophora resemble those of Phialophora in having melanized thalli with intercalary or terminal phialides bearing collarettes, but Phialophora has aseptate conidia whereas Cyphellophora produces larger, fusiform to sigmoid, aseptate to multi-septate conidia (Réblová et al. 2013). Cyphellophora can also be compared to Pseudomicrodochium, the former having melanized thalli while they are hyaline in Pseudomicrodochium (Decock et al. 2003; de Hoog et al. 2009, 2011). Yang et al. (2018) introduced C. jingdongensis the first sexual morph, which is characterized by subglobose to globose, non-ostiolate ascomata, ellipsoidal to cylindrical asci and fusoid, 1–3 septate ascospores. However, the asexual morph of C. jingdongensis was difficult to observe in culture to compare with other species in Cyphellophora (Yang et al. 2018). There are 26 epithets of Cyphellophora in Index Fungorum (2019). Yang et al. (2018) clarified 23 species in this genus. To properly delineate these species, phylogenetic studies using multi-loci sequences (ITS, LSU, RPB1 and TUB2) and the secondary structures of ITS analyses are needed (Réblová et al. 2013; Feng et al. 2014; Gao et al. 2015; Yang et al. 2018).

Molecular based identification and diversity

Based on SSU and LSU sequence data, Cyphellophora clustered in a well-supported clade within the Chaetothyriales (Feng et al. 2014). Generic and species delimitation with morphological characters, ecological traits, host distribution and phylogenetic analyses using the internal transcribed spacer region (ITS), the partial β-tubulin gene (TUB2), the nuclear large subunit rDNA gene (LSU) and the DNA dependent RNA polymerase II largest subunit (RPB1) were recently performed (Feng et al. 2014; Gao et al. 2015). The present study reconstructs the phylogeny of Cyphellophora based on analyses of combined ITS, TUB2, LSU and RPB1 sequence data (Table 4, Fig. 9). The phylogenetic tree in this study is updated with recently introduced Cyphellophora species and corresponds to previous studies (Feng et al. 2014; Gao et al. 2015). Cyphellophoroa indica and C. taiwanensis lack sequences in GenBank (4/7/2019). Cyphellophoroa hylomeconis was synonymized as Camptophora hylomeconis and C. eugeniae was synonymized as Aphanophora eugeniae (Réblová et al. 2013). Cyphellophoroa eucalypti were synonymized as C. guyanensis (Feng et al. 2014). Therefore, these species were not included in the present phylogenetic analyses (Fig. 9).

Recommended genetic markers (genus level) – LSU and SSU

Recommended genetic markers (species level) – ITS, LSU, TUB2, RPB1 and secondary (2D) structure of ITS analyses

LSU is useful for preliminary identification at the generic level (Feng et al. 2014). Réblová et al. (2013) resolved Cyphellophora and Phialophora as close relatives within the Chaetothyriales, although both genera were paraphyletic based on analysis of ITS, TUB2 and nuc28S rDNA sequence data. It is recommended to use a combination of ITS, LSU, TUB2, RPB1 and secondary (2D) structure of ITS analyses (Réblová et al. 2013; Feng et al. 2014; Gao et al. 2015) in order to identify to the species level.

Accepted number of species: 24 species

References: Vries 1962, 1986; Matsushima 1987; Walz and Hoog 1987; Decock et al. 2003; Crous et al. 2013, 2016; Réblová et al. 2013; Feng et al. 2014; Gao et al. 2015; Madrid et al. 2016; Yang et al. 2018 (morphology, phylogeny)