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
Bahusakala Subram., J. Indian bot. Soc. 37: 63 (1958)
Pathogenic on leaves in terrestrial habitat. Sexual morph: Undetermined. Asexual morph: Hyphomycetous. Mycelium hairy, dense, partly immersed, partly superficial, congested, effuse, composed of branched, septate, thick-walled, olive-black hyphae. Stroma none. Setae and hyphopodia absent. Conidiophores distinct, solitary, macronematous, mononematous, arthric, erect, branched, cylindrical, smooth to verruculose, septate, thick-walled, producing arthroconidium. Conidiogenous cells holothallic, terminal, integrated, brown, smooth, 8 µm long, 3 µm wide at the tip. Conidia simple, more or less cylindrical or oblong, brown or dark brown, smooth, wrinkled or verrucose with one or more transverse septa.
Type species – Bahusakala olivaceonigra (Berk. & Broome) Subram.
Notes – Bahusakala olivaceonigra is the type species of genus Bahusakala, which comprises six species (Index Fungorum 2019). According to Seifert et al. (2011), the genus Bahusakala probably has sexual morphs in Aulographina (Asterinaceae, Dothideomycetes) or Xylogone (Leotiomycetes) but this information warrants further studies. This fungus can be found in areas with a wide range of climatic conditions (Farr & Rossman 2017) and has been reported to cause leaf blight disease of the sisal (Agave sisalana). In this study, we re-examined the holotype specimen of Bahusakala olivaceonigra. We also did phylogenetic analysis using the putative strains of Bahusakala longispora CBS 544.84. The latter forms a distinct clade in the Sordariomycetes with low bootstrap support (Fig. 68). Species of Bahusakala resemble Parasympodiella in having distinct, single conidiophores with terminal and intercalary, integrated, indeterminate, sympodially extending, conidiogenous cells that produce catenate, cylindrical, thallic conidia by disarticulations of the fertile branches. Parasympodiella is accommodated in its own family Parasympodiellaceae, Parasympodiellales (Hernández-Restrepo et al. 2017). We place the genus Bahusakala in Sordariomycetes, genera incertae sedis.
Figure 68 – Phylogram generated from maximum likelihood analysis based on combined LSU, sequence data retrieved from the GenBank. Related sequences were referred to Liu et al. (2017). Eleven taxa are included in the genes sequence analyses which comprise total 923 characters after alignment. Gyromitra californica (AFTOL 176) and Cheilymenia stercorea (AFTOL 148) 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 -4643.563264 is presented. Estimated base frequencies were as follows: A = 0.252550, C = 0.217382, G = 0.308330, T = 0.221738; substitution rates AC = 0.405017, AG = 1.017741, AT 0.509145, CG = 0.483871, CT = 4.087105, GT = 1.000000; gamma distribution shape parameter α = 0.580334; proportion of invariant 0.318519. 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.