New nematicidal and antimicrobial secondary metabolites from a new species in the new genus, Pseudobambusicolathailandica Author Rupcic, Zeljka Author Chepkirui, Clara Author Hernandez-Restrepo, Margarita Author Crous, Pedro W. Author Luangsa-ard, Janet Jennifer Author Stadler, Marc text MycoKeys 2018 33 1 23 http://dx.doi.org/10.3897/mycokeys.33.23341 journal article http://dx.doi.org/10.3897/mycokeys.33.23341 1314-4049-33-1 Pseudobambusicola thailandica Hern.-Restr. & Crous sp. nov. Etymology. The epithet refers to Thailand, where this species was collected. Type. THAILAND. Lop Buri Province: Chai Badan, Wang Kan Lueang Arboretum, Wang Kan Lueang Waterfall, on twig (unidentified), 14 Jul 2015, M. Hernandez-Restrepo , MHR 1534 (holotype: BBH 42022!, culture ex-type BCC 79462!). Description of fungal structures on SNA. Mycelium composed by hyaline to pale brown, septate, smooth to slightly verruculose, hyphae, 1-2.5 µm wide. Conidiomata pycnidial, semi- or entirely immersed in the agar, solitary or aggregated, erumpent, globose, sometimes with a neck, opening via central ostiole, dark brown, 63-360 µm diam., sometimes with a cylindrical neck 50-125 x 40-50 µm , opening via central ostiole; at the base of the conidiomata are often present globose to subglobose cells, thick-walled, 5-9 µm wide; conidiomata surrounded by dark brown, smooth to slightly verruculose hyphae, 2-2.5 µm wide. Conidiophores reduced to conidiogenous cells. Conidiogenous cells phialidic with periclinal thickening, subcylindrical to ampulliform, hyaline, smooth, 6.5-7 x 2.5-4 µm . Conidia exposed in white, mucous drops at the ostiole of pycnidia, composed by macro- and microconidia. Macroconidia produced in white, mucous heads, solitary, fusoid-ellipsoid, apex bluntly to subobtusely rounded, tapering to a distinctly truncate base, mostly straight, but sometimes slightly curved, prominently guttulate, hyaline, smooth, 0-3-septate, 10-20 x 2 -4(- 6) µm . Microconidia produced in the same pycnidia with macroconidia, solitary, oblong to cuneiform, non-guttulate to slightly guttulate, hyaline, smooth, aseptate, 2 -4(- 5.5) x 1-2 µm , apex rounded, base truncate. Chlamydospores brown, terminal, in chains, 16-38 x 5-6 µm . Sexual morph not observed. Culture characteristics. Colonies on OA at 25 °C reaching 24 mm diam. in 2 weeks, elevated, with dense cottony mycelium at the centre, mouse grey, margin whitish, effuse to fimbriate; reverse dark mouse grey. Notes. Pseudobambusicola is introduced here for a pycnidial coelomycete producing two kinds of conidia. Morphologically, it is similar to the species of Bambusicola and Neobambusicola . However, asexual morphs in Bambusicola are characterised by brown or pale brown conidia and annellidic rather than phialidic conidiogenous cells and hyaline conidia as in Pseudobambusicola ( Dai et al. 2012 , 2017 ). Neobambusicola is a monotypic genus erected for N. strelitziae , first described from South Africa growing on necrotic leaf tissue associated with Phyllachora strelitziae ( Phyllachoraceae , Phyllachorales , Sordariomycetes ) ( Crous et al. 2014 ). Both genera are similar in having pycnidial conidiomata and phialidic conidiogenous cells that produce fusoid-ellipsoid macro- and subcylindrical microconidia. However, in the new genus, the conidiomata are surrounded by dark brown, smooth to slightly verruculose hyphae and, in mature conidiomata, a cylindrical neck is often present; furthermore, chlamydospores can be present in culture. Although both genera belong to the Sulcatisporaceae ( Pleosporales , Dothideomycetes ), they are placed in different clades, Neobambusicola is more closely related to Sulcatispora (100 %, 1 pp), while Pseudobambusicola was placed in a distinct branch with Magnicamarisporium (Fig. 1). Additionally, based on LSU, ITS and tef1 sequences, P. thailandica is 97 % (KP004495) and 83 % (KP004467) and 93 % similar to N. strelitziae , respectively. Figure 2. Pseudobambusicola thailandica (BCC 79462) on SNA. A Colony overview B-C Pycnidia D-G Conidiogenous cells H globose to subglobose cells, thick-walled, at the base of the conidiomata I Microconidia J Macroconidia K Chlamydospores . Scale bars: 200 µm (B), 100 µm (C), 10 µm (D, H, I-K ), 5 µm ( E-G ).