Ernakulamia tanakae Rajeshkumar & K.D. Hyde, Fungal Diversity 100: 111 (2020)

Index Fungorum number: IF 556700; MycoBank number: MB 556700; Facesoffungi number: FoF 06338; Fig. 1

Saprobic on decaying wood. Sexual morph Undetermined. Asexual morph Hyphomycetous. Colonies effuse, superficial, dark brown to black, sparsely hyaline hyphal network. Conidiophores not seen. Conidiogenous cells monotretic, integrated. Conidia 35–48 × 22–37 µm (x̅=42×30 µm, n=10), dictyosporous, obconical, obovoid or subglobose, dark brown, multi-septate, thick-walled, with 3–5-appendages per conidium. Appendages 24–68×4–5 µm, cylindrical stiff, straight, apical or subapical, dark brown, 3–6-septate, smooth-walled.

Culture characteristics – Conidium germinating on PDA within 24 h. Colonies on PDA reaching 3.5 cm diam. after 2 weeks at room temperature, circular, undulate edge, grey to dark grey, dense and raised on medium surface. Mycelium superficial, velvety, flossy.

Material examined – THAILAND, Phetchabun Province, Lom Sak, saprobic on decaying wood of unidentified host, 25 July 2019, S. Boonmee, LSP02 (MFLU 21-0066, new record), living culture, MFLUCC 21-0089.

GenBank numbers – ITS=MZ538502, LSU=MZ538536, TEF1-α=MZ567081.

Notes – Ernakulamia tanakae was introduced by Hyde et al. (2020a), which is reported as a second species found on the Cocos nucifera host from India as well as the type species E. cochinensis. All species of Ernakulamia are characterized by superficial, dictyosporous, with cylindrical stiff appendages and dark brown conidia (Fig. 1, Subramanian 1994; Jayasiri et al. 2019; Hyde et al. 2020b). Phylogenetic analysis placed our strain (MFLUCC 21-0089) close to the type strain (NFCCI 4615) and other isolates of E. tanakae (NFCCI 4616 and NFCCI 4617) (Fig. 2). Pairwise comparison of DNA sequences of LSU and ITS regions of these four strains reveals 2/872 bp (0.23%) and 5/528 bp (0.95%) very few base pair differences, which confirms that they are conspecific. Thus, a new geographical record of E. tanakae on decaying wood from Thailand is reported.

Figure 1 – Ernakulamia tanakae (MFLU 21-0066, new record). a, b Appearance of conidial masses on host substrate. c–f Mature conidia. g Germinated conidium. h, i Culture on PDA from surface and reverse. Scale bars: c–f=10 µm, g=20 µm

Figure 2 – Maximum likelihood phylogenetic tree based on a combined LSU and ITS sequence dataset of Ernakulamia taxa and related genera in Tetraplosphaeriaceae. Thirty-eight strains are included in the combined analyses which comprise a total of 1468 characters. Amniculicola immersa (CBS 12308) and A. parva (CBS 123092) are selected as the outgroup taxa. The best RAxML tree with a final likelihood value of − 5624.746373 is presented. RAxML analysis yielded 413 distinct alignment patterns and 15% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.236603, C=0.245429, G=0.293755, T=0.224212, with substitution rates AC=2.551620, AG=2.407140, AT=1.683194, CG=0.618325, CT=9.671311, GT=1.000000; gamma distribution shape parameter alpha=0.164106. Bootstrap support values for maximum likelihood (MLBS, left) equal to or greater than 70% are given above or below 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