Three novel species and new records of Kirschsteiniothelia (Kirschsteiniotheliales) from northern Thailand.

Kirschsteiniothelia (Kirschsteiniotheliales, Pleosporomycetidae) includes 39 saprobic species recorded from dead or decaying wood in terrestrial and freshwater habitats. This study focuses on exploring Kirschsteiniothelia diversity in woody litter in Thailand. Wood samples were collected from forest areas in Chiang Rai and Chiang Mai Provinces in Thailand and examined for fungal fructifications. Fungal isolates were obtained and their morphological and sequence data were characterised. Micromorphology associated with multilocus phylogeny of ITS, LSU and SSU sequence data identified three isolates as novel species (Kirschsteiniotheliainthanonensis, K.saprophytica and K.zizyphifolii) besides new host records for K.tectonae and K.xishuangbannaensis. The placement of the new taxa and records are supported by morphological illustrations, descriptions and molecular phylogenies and the implications of these findings are discussed. Our findings provide information for understanding Kirschsteiniothelia diversity and ecology.

Additions to Diatrypaceae (Xylariales): Novel Taxa and New Host Associations.

Diatrypaceae members have a broad distribution and are commonly found on decaying wood. Despite taxonomic and morphological challenges within this group, there has been a growing interest in Diatrypaceae in recent years. The dead branches of several plant hosts with fungal fruiting bodies were collected from Doi Tung National Park, Chiang Rai, and the Narathiwat Provinces in Thailand. Their morphological characteristics, coupled with a molecular phylogeny of combined ITS and tub2 sequence data, were used to introduce two novel Allodiatrype species (A. dalbergiae and A. eleiodoxae) and one new Melanostictus species (M. chiangraiensis). Moreover, four new host records, Diatrypella heveae, D. major, Melanostictus thailandicus, and Paraeutypella citricola on Microcos paniculata, Nayariophyton zizyphifolium, Dalbergia cultrata, and M. paniculata, respectively, as well as a new geographical record of D. major are reported. This research provides detailed descriptions of macro- and microcharacteristics, coupled with a phylogenetic tree for the newly introduced species and host records. The morphological features of Allodiatrype and Melanostictus are listed in the synoptic table.