Chaetosphaeriales Huhndorf, A.N. Mill. & F.A. Fernández, Mycologia 96(2): 378 (2004)

Index Fungorum number: IF 501514; MycoBank number: MB 501514; Facesoffungi number: FoF 09685;

Huhndorf et al. (2004) introduced this order for Chaetosphaeriaceae. Linocarpaceae was added to Chaetosphaeriales by Konta et al. (2017) to accommodate Neolinocarpon and Linocarpon, which are previously accepted in Xylariales, genera incertae sedis (Maharachchikumbura et al. 2015, 2016b). Konta et al. (2017) also established Leptosporellaceae to accommodate Leptosporella, which was maintained in Chaetosphaeriales genera incertae sedis by Maharachchikumbura et al. (2016b). Wijayawardene et al. (2018a) accepted Leptosporellaceae and Linocarpaceae in Chaetosphaeriales, and this is confirmed in our phylogenetic analysis (Figs. 1, 8). The polyphyletic genus Diplococcium was previously excluded from Sordariomycetes and accepted in Helotiales by Maharachchikumbura et al. (2015). Wijayawardene et al. (2018a) listed Diplococcium in Helminthosphaeriaceae. However, a phylogenetic analysis by Hernández-Restrepo et al. (2017) confirmed that Diplococcium is not related to Helminthosphaeriaceae and was placed in Helotiales. Lin et al. (2019) introduced Multiguttulispora and placed it within Chaetosphaeriaceae. Neoleptosporella (incertae sedis) will be added to the order by Phukhamsakda et al. (2020). Chaetosphaeriales grouped sister to Tracyllalales with low statistical support in our phylogenetic analysis (Figs 1, 8). The divergence time for Chaetosphaeriales has been estimated as 158 MYA (Fig. 2). Here, we accept four families and 59 genera in the order.

Figure 1 – Maximum likelihood (ML) majority rule combined LSU, SSU, tef1 and rpb2 consensus tree for the analyzed Sordariomycetes isolates. Families are indicated in yellow and green coloured blocks and orders are indicated in dark and light grey coloured blocks. RAxML bootstrap support values (MLB above 50 %) are given at the nodes. The scale bar represents the expected number of changes per site. The tree is rooted with Botryotinia fuckeliana (AFTOL ID-59), Dothidea sambuci (DAOM 231303), and Pyxidiophora arvernensis (AFTOL-ID 2197).

Figure 1 – Continued.

Figure 1 – Continued.

Figure 2 – The maximum clade credibility (MCC) tree, using the same dataset from Fig. 1. This analysis was performed in BEAST v1.10.2. The crown age of Sordariomycetes was set with Normal distribution, mean = 250, SD = 30, with 97.5% of CI = 308.8 MYA, and crown age of Dothideomycetes with Normal distribution mean = 360, SD = 20, with 97.5% of CI = 399 MYA. The substitution models were selected based on jModeltest2.1.1; GTR+I+G for LSU, rpb2 and SSU, and TrN+I+G for tef1 (the model TrN is not available in BEAUti 1.10.2, thus we used TN93). Lognormal distribution of rates was used during the analyses with uncorrelated relaxed clock model. The Yule process tree prior was used to model the speciation of nodes in the topology with a randomly generated starting tree. The analyses were performed for 100 million generations, with sampling parameters every 10000 generations. The effective sample sizes were checked in Tracer v.1.6 and the acceptable values are higher than 200. The first 20% representing the burn-in phase were discarded and the remaining trees were combined in LogCombiner 1.10.2., summarized data and estimated in TreeAnnotator 1.10.2. Bars correspond to the 95% highest posterior density (HPD) intervals. The scale axis shows divergence times as millions of years ago (MYA).

Figure 2 – Continued.

Figure 2 – Continued.

Figure 8 – Phylogram generated from maximum likelihood analysis based on combined LSU and ITS sequence data of Chaetosphaeriales and Tracyllalales taxa. Ninety-six strains are included in the combined analyses which comprised 1695 characters (1081 characters for LSU, 614 characters for ITS) after alignment. Neurospora crassa MUCL 19026 and Gelasinospora tetrasperma CBS 178.33 (Sordariaceae, Sordariales) are used as outgroup taxa. Single gene analyses were carried out and the phylogenies were similar in topology and clade stability. Tree topology of the maximum likelihood analysis is similar to the Bayesian analysis. The best RaxML tree with a final likelihood value of – 23777.689886 is presented. Estimated base frequencies were as follows: A = 0.231060, C = 0.264793, G = 0.308265, T = 0.195882; substitution rates AC = 1.388486, AG = 1.836207, AT = 1.649563, CG = 0.971659, CT = 6.316962, GT = 1.000000; gamma distribution shape parameter a = 0.460297. Bootstrap support values for ML greater than 75% and Bayesian posterior probabilities greater than 0.95 are given near the nodes. Ex-type strains are in bold. The newly generated sequences are indicated in blue.

Figure 8 – Continued.

Families

Chaetosphaeriales genera incertae sedis