Evansstolkia Houbraken, Frisvad & Samson, gen. nov.
Index Fungorum number: MB832553; Facesoffungi number: FoF 12967
Etymology: Named after H.C. Evans and A.C. Stolk, the authors of the sole species in this genus.
Diagnosis: Phylogenetically distinct. Conidiophores paecilomyces-like; conidia brown; chlamydospores present, thick-walled; ascospores decorated with somewhat jagged, irregular, mostly longitudinal ridges of different lengths. Thermotolerant to thermophilic. Fig. 5.
Type: Evansstolkia leycettanum H.C. Evans & Stolk
Notes: – Evansstolkia forms a single lineage and is a monotypic genus, containing the species Talaromyces leycettanus (basionym: Penicillium leycettanum). Talaromyces leycettanus was originally classiﬁed in Talaromyces because of the production of ascomata that are surrounded by a deﬁnite network of pale yellow hyphae and the production of asci in chains. In contrast to these observations, Houbraken & Samson (2011) noted that this species phylogenetically belongs to the Aspergillaceae, instead of the Trichocomaceae, and this observation is conﬁrmed in this study. Talaromyces leycettanus is phylogenetically most closely related to Hamigera striata (88 % BS, Fig. 1).
This species produces paecilomyces-like conidiophores, brown-coloured conidia, thick-walled chlamydospores and ascospores that are decorated with somewhat jagged, irregular, mostly longitudinal ridges of different lengths. Furthermore, Tal. leycettanus is thermotolerant to thermophilic. This combination of characters is unique in the Aspergillaceae and we, therefore, decided to accommodate this species in a novel genus.
Fig. 1. Combined phylogeny using nine loci (RPB1, RPB2, Cct8, Tsr1, CaM, BenA, SSU, LSU, ITS). Clades in the phylogram are collapsed showing the relationship between genera and families in the Eurotiales. The phylogram is based on 263 species belonging to the order Eurotiales and 16 species from the order Onygenales (used an outgroup). The species used in the analysis can be found in Supplementary Fig. S1 and Supplementary Table S1.
Fig. 5. Morphological characters of Evansstolkia leycettana (CBS 398.68T). A. Colonies from left to right, after 7 d at 37 °C unless stated otherwise (top row) MEA 25 °C, MEA, YES, OA; (bottom row) CYA 25 °C, CYA, DG18, CREA. B– C. Conidiophores and conidia. D. SEM micrograph of ascospores. Scale bars: B–C = 10 μm; D = 1 μm.