A re-assessment of Elsinoaceae (Myriangiales, Dothideomycetes)

Abstract

The family Elsinoaceae is a relatively poorly known, but important family within Myriangiales, Dothideomycetes. The genera of this family are mostly plant pathogens and causes disease, such as apple and grape scab. In this paper we revisit the family by examining generic types and analysis of molecular sequence data available in GenBank. Elsinoaceae and Myriangeaceae are morphologically and phylogenetically well-supported families in Myriangiales. In Elsinoaceae, 3 to 10 asci form in locules in light coloured pseudoascostromata, which form typical scab-like blemishes on leaf or fruit surfaces, while Myriangeaceae forms raised, superficial, black ascostromata with single asci in each locule, genera may or may not form scab-like lesions. Elsinoe is the type of the family Elsinoaceae and is characterized by forming scab-like blemishes on leaves with few to numerous bitunicate, fissitunicate, globose asci forming inside each locule with a pseudoascostroma containing fungal and host tissues. Following examination of generic type material, Molleriella is retained in Elsinoaceae as it has characters similar to Elsinoe in forming scab-like lesions with pseudoascostromata containing few to numerous bitunicate asci inside each locule. Beelia, Butleria, Hemimyriangium, Hyalotheles, Micularia, Saccardinula, Stephanatheca and Xenodium are excluded from Elsinoaceae and their relative placement in Dothideomycetes is discussed. Fresh collections of these genera are needed so that molecular sequence data can be obtained and analysed to resolve their placement in families or orders of Dothidoemycetes.

Trichopeltinaceae (Dothideomycetes), an earlier name for Brefeldiellaceae, with a new species of Trichopeltina

“…We treat Brefeldiellaceae as a synonym of Trichopeltinaceae. The family differs from Stephanothecaceae which has individual thyriothecia with hypostromata (Jayawardena et al 2014). Stephanothecaceae may need resurrecting to accommodate Stephanatheca and similar genera, as its fruiting structures are quite unusual in Dothideomycetes (Hyde et al 2013).…”

“…Hyde et al (2013) placed Pycnoderma in Brefeldiellaceae and also placed the genus in Cookellaceae in the same publication; we agree to it being placed in Cookellaceae based on its thyriothecia clustered together with surface rough, pigmented. Pycnoderma is similar to Saccardinula based on its muriform ascospores, but the thallus is less well-developed than in Saccardinula (Jayawardena et al 2014, Spegazzini 1885, while thyriothecia of Pycnoderma cluster together, with globose asci. Pycnoderma is also similar to Elsinoaceae species based on globose asci, but Elsinoaceae species have wart-like ascostromata, or are small, white to pale yellow or brown, soft, and multi-loculate (Hyde et al 2013).…”

“…However, Stephanothecaceae (type genus Stephanotheca) has a hypostroma, and was considered to be distinct from Trichopeltinaceae (Bessey 1952, Batista et al 1958. Stephanotheca was illustrated by Jayawardena et al (2014), but the thyriothecia are individual and not covered by a thallus, and thus are probably distinct from Trichopeltina. Epiphytes on leaves, appearing as "root"-like darkened areas.…”

“…Thyriothecia in Microthyriaceae and Stephanothecaceae do not develop under a spreading thallus (Bessey 1952, Batista et al 1958, Jayawardena et al 2014, unlike in Trichopeltinaceae. However, the families need further study.…”

Prillieuxina citricola sp. nov. from Himachal Pradesh, India

“…The asci formed in Schenckiella are rarely observed in the Dothideomycetes. Different dothideomycetes like Elsinoe fawcettii (Jayawardena et al 2014), Polychaeton citri and Pseudocercospora angolensi (Schoch et al 2009) have been reported to cause scab and anthracnose on various Citrus spp.…”