Citation: Pem D et al. (2019) Mycosphere Notes 275-324: A morphotaxonomic revision and typification of obscure Dothideomycetes genera (incertae sedis). Mycosphere 10(1), 1115–1246
Gibberidea Fuckel, Jb. nassau. Ver. Naturk. 23-24: 168 (1870) [1869-70]
= Sphaeropsis Sacc., Michelia 2(no. 6): 105 (1880)
Saprobic or pathogenic on stem. Sexual morph: See Phillips et al. (2013). Asexual morph: Conidiomata immersed to semi-immersed, unilocular, subglobose. Peridium composed of dark brown cells of textura angularis. Paraphyses hyaline, aseptate, up to 50 µm long and 2 µm wide, with a bulbous tip 5 µm diam. Conidiogenous cells enteroblastic, hyaline, discrete proliferating internally to form periclinal thickenings. Conidia oval, apex obtuse to rounded, base obtuse or truncate, moderately thick-walled, initially hyaline, becoming brown, externally smooth-walled, internally finely verruculose-walled.
Type species – Gibberidea visci Fuckel
Notes – The genus Gibberidea was introduced as a monotypic genus by Fuckel (1870). The genus Gibberidea is given as a synonym of Botryosphaeria Ces. & De Not. in Index Fungorum (2019). Wijayawardene et al. (2017) placed Gibberidea in Dothideomycetes, genera incertae sedis. We could not examine the type material, but studied a specimen of Gibberidea visci from ILL herbarium. Based on morphology, it seems that the genus Gibberidea is a synonym of Sphaeropsis (Phillips et al. 2008, 2013). Phillips et al. (2013) considered Phaeobotryosphaeria as a synonym of Sphaeropsis and the older name Sphaeropsis is used based on the one fungus-one name concept. The genus Gibberidea is characterized by immersed to semi-immersed conidiomata and hyaline to brown ascospores. It seems clear that the genus Gibberidea should be placed in Botryosphaeriaceae and is a synonym of Sphaeropsis. In our analyses (Fig. 2), the strains Phaeobotryosphaeria visci CBS 186.97 and CBS 100163 cluster in Botryosphaeriaceae. We therefore, agree with Phillips et al. (2008) and exclude Gibberidea from Dothideomycetes genera incertae sedis.
Figure 2 – Phylogram generated from maximum likelihood analysis based on LSU sequence data retrieved from the GenBank. Related sequences were retrieved from Liu et al. (2017). Twenty four taxa are included in the analyses which comprise 965 characters after alignment. Phyllosticta ampelicida, Phyllosticta capitalensis and Phyllosticta citricarpa are used as the out-group taxa. Maximum likelihood (ML) analysis was conducted in the CIPRES Science Gateway V. 3.3. The best sorting RaXML tree with a final likelihood value of -2440.002151 is presented. Estimated base frequencies were as follows: A = 0.255123, C = 0.215800, G = 0.310407, T = 0.218670; substitution rates AC = 1.413575, AG = 4.032008, AT = 1.495545, CG = 0.857086, CT = 13.775815, GT = 1.000000; gamma distribution shape parameter α = 0.020000; proportion of invariant 0.246495. ML bootstrap values ≥ 50% are given as the first set of numbers and approximate likelihood-ratio test (aLRT) ≥ 0.90 values as the second set of numbers above the nodes. Voucher/strain numbers are given after the taxon names, the one from type material are indicated in bold face. Sequence of interest is indicated in red. The bar length indicates the number of nucleotide substitutions per site.