AbstractIn recent years, several species that have long been considered to belong in Bacidia s. lat. have been transferred to other genera such as Bellicidia, Bibbya, Scutula, and also to Toniniopsis, accommodating species previously placed in Bacidia and Toninia. One of its widespread species, Toniniopsis subincompta, can be recognized by its thinly granular thallus, dark brown to black apothecia, green epithecium, red-brown hypothecium, and bacilliform ascospores. However, it shows considerable variation in thallus structure, and coloration of apothecia, hypothecium and exciple. We sequenced 20 specimens of T. subincompta to investigate whether there is phylogenetic support for the delimitation of species in accordance with the variability of the observed characters. For phylogenetic analyses, we used newly generated sequence data from the nuclear internal transcribed spacer (nrITS), mitochondrial small subunit (mtSSU) and DNA-directed RNA polymerase II subunit (RPB2). Maximum likelihood and Bayesian inference analyses, as well as three species delimitation programs, provided consistent evidence that T. subincompta forms two separate lineages, to be recognized at the species level. The complex nomenclature of T. subincompta (basionym Lecidea subincompta) shows it to be a synonym of Bellicidia incompta. For the most common taxon previously called Bacidia (Toniniopsis) subincompta, the new combination T. separabilis is made, rather than proposing a conserved type for Lecidea subincompta. Toniniopsis dissimilis is newly described to accommodate the less common taxon. Toniniopsis dissimilis is characterized by a predominantly wrinkled to warted to subsquamulose thallus; generally grey-brown to dark brown apothecia, often with a lighter margin; a dark brown hypothecium, frequently gradually merging into the coloration of the exciple below and the lateral part of the exciple attached to the hymenium; a mostly colourless rim and lateral part of the exciple. The closely related T. separabilis is characterized by a thallus of mostly single or contiguous ±loose granules, often forming short, coralloid, isidium-like bulges; darker apothecia, with a margin mostly of the same colour or darker than the disc; a comparatively thinner hypothecium easily separated from the exciple below. The rim and lateral part of the exciple often contain either a blue, brown or mixed blue-brown colour in the upper part or along the whole margin. Lectotypes of Bacidia vegeta, Lecidea bacillifera f. melanotica and Secoliga atrosanguinea var. affinis (the synonyms of T. separabilis) are selected. Cyanotrophy and the occurrence of albino morphs in T. separabilis are discussed.
New host associations and a novel species for the gall-inducing acacia rust genus Ravenelia in South Africa