Ascoma Development in Neophyllis melacarpa (Lecanorales, Ascomycota), with Notes on the Systematic Position of the Genus

Abstract

The ascoma ontogeny of Neophyllis melacarpa (F.Wilson)F.Wilson is described and similarities toAustropeltum glareosum Henssen, Döring & Kantvilas are pointed out. Neophyllis is shown to formtrue podetia as well as pseudopodetia, and an unpigmented boundary tissue ofthin-walled, plasma-rich hyphae. Characteristic features include the formationof a boundary tissue separating a hypophysiate pseudopodetium from theascomatal tissue, a large subglobose hypothecium, and a cortical covering ofyounger developmental stages. Ascus structure and conidiophore anatomy aredescribed and similarities to Austropeltum arediscussed. The secondary product chemistry of Neophyllisis described in detail, and two chemical taxa, corresponding to the currentlyaccepted species N. melacarpa andN. pachyphylla (MÜll.Arg.) Schneider, aretentatively accepted. The systematic position ofNeophyllis is discussed, and the generic distinctnessfrom Gymnoderma is clarified. It is concluded thatNeophyllis is closely related toAustropeltum, and that there is no support for regardingNeophyllis as closely related toCladonia, the generic type of Cladoniaceae. The possibleaffinities of Neophyllis to Stereocaulaceae andSphaerophoraceae are discussed, but it is pointed out that the delimitation ofall three families needs further investigation.