Megacapitula J.L. Chen & Tzean

Index Fungorum number: IF 25546; MycoBank number: MB 25546; Figs. 1

Notes – Megacapitula was introduced to accommodate a single species M. villosa which was found on an unidentified fallen decayed petiole in Taiwan by Chen and Tzean (1993). There is no sequence data available. The genus is characterized by obclavate or ellipsoidal to obpyriform, darkly pigmented conidia, crowned with densely packed hairy, brown apical appendages (Chen and Tzean 1993; Delgado 2010). Prabhugaonkar and Bhat (2011) later provided ITS sequence for an isolate of M. villosa collected from dead fronds of palm Caryota urens (Arecaceae) in India. Phylogenetic analysis with only ITS sequence data indicated that M. villosa (GUFCC 15515) clustered with an unidentified endophyte strain P1802A and basal to other genera of Pleosporales (Prabhugaonkar and Bhat 2011). In addition, there are two unpublished sequences of M. villosa AL4 and cp053a that are available in GenBank databases but no morphological descriptions. In this study, we introduce the new record Megacapitula villosa which was isolated from submerged decaying wood in a small freshwater stream in Thailand and provide an updated phylogenetic tree for Megacapitula (Fig. 1).

Figure 1 – Maximum likelihood phylogenetic tree based on a combined LSU and ITS sequence dataset of Megacapitula taxa and related families in Pleosporales. Sixty-seven strains are included in the combined analyses which comprise a total of 1456 characters. Cyclothyriella rubronotata CBS 385.39 is selected as the outgroup taxon. The best RAxML tree with a final likelihood value of − 12939.878192 is presented. RAxML analysis yielded 723 distinct alignment patterns and 29.63% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.242721, C=0.238518, G=0.291320, T=0.227442, with substitution rates AC=1.943333, AG=2.988826, AT=2.324598, CG=1.416039, CT=8.575259, GT=1.000000; gamma distribution shape parameter alpha=0.245601. Bootstrap support values for maximum likelihood (MLBS, left) equal to or greater than 70% is given above the nodes. Bayesian posterior probabilities (BYPP, right) equal to or greater than 0.95 are given above the nodes. Ex-type strains are in bold and newly generated sequence is in blue

Species