Thyronectria caudata (Malençon) Jaklitsch & Voglmayr, Persoonia 33: 195 (2014)

Index Fungorum number: IF 808296; MycoBank number:  MB 808296; Facesoffungi number: FoF 09960; Fig. 1

≡ Thyronectria lamyi var. caudata Malençon, Bull. Trimestriel Soc. Mycol. France 95: 99 (1979)

Saprobic on woody twigs. Sexual morph Ascomata 280–380 µm high, 300–400 µm diam. (x̅=329×356 µm, n=15), superficial on the hypostroma, not surrounded by bark flaps, aggregated in round or elongated clusters, rarely solitary, globose to obovoid, rarely cupulate when dry, reddish brown. Ostiole central, slightly papillate or flat-umbilicate, periphysate. Peridium 30–60 µm wide, widest at the apex, composed of several layers of yellowish-brown cells of textura angularis. Hamathecium comprising numerous, 1.5–3.5 µm wide, filamentous, rarely branched, hyaline, paraphyses. Asci 90–120×15–25 µm (x̅=103.5×19 µm, n=15), 8-spored, unitunicate, cylindrical to clavate, pedicellate, rounded at the apex, mostly filled with ascoconidia when mature. Ascospores 20–28×4–6 µm (x̅=24×5 µm, n=30), 1–2-seriate, overlapping, narrowly clavate, with 6–10 transverse septa and 1 longitudinal or oblique septum in 1 or few cells of, all cells budding to produce oblong, 1-celled, hyaline, straight to slightly curved ascoconidia 3.5–5×1–1.5 µm (x̅=4×1 µm, n=40). Asexual morph Undetermined.

Material examined – UZBEKISTAN, Jizzakh Province, Zaamin District, Zaamin National Nature Park, river of Uriklisoy, Turkestan range of Pamir-Alay Mountains, on dead stems of Berberis oblonga (Regel) C.K. Schneid (Berberidaceae), 13 July 2019, Yusufjon Gafforov YG-Z54-1 (TASM 6160, KUN-HKAS 115784, new record); ibid., 13 July 2019, Y. Gafforov and T. Kholmuradova, YG-Z54-2 (TASM 6161, KUN-HKAS 115785).

GenBank numbers – ACT = MZ508400, MZ508401, ITS = MZ493292, MZ493293, LSU = MZ493306, MZ493307, TEF1-α=MZ508402, MZ508403.

Notes – Thyronectria caudata was initially introduced as Thyronectria lamyi var. caudate by Malençon (1979). Jaklitsch and Voglmayr (2014) synonymized this as the Thyronectria caudata. Morphological features (Fig. 1) of TASM 6160 and TASM 6161 are similar to those in the holotype of Thyronectria caudata. These collections were all made from the same host genus (Berberis) but in different locations. Phylogenetically, TASM 6160 and TASM 6161 are closely related to Thyronectria berberidicola (Ma et al. 2020) in the multi-gene concatenated tree (Fig. 2). However, this species does not deposit in MycoBank or Index Fungorum. Ma et al. (2020) introduced Thyronectria berberidicola from the Xinjiang Uygur Autonomous Region in China and the morphological features between Thyronectria caudata and this species results in no outstanding differences. We reckon the collections made by Ma et al. (2020) should also belong to Thyronectria caudata.

Figure 1 – Thyronectria caudata (TASM 6160, KUN-HKAS 115784, new record). a, b Perithecial aggregates on host surface. c Longitudinal section of a perithecium. d Section of the peridium cells. e Paraphyses. f–h Asci. i, j Ascospores. k Ascoconidia. Scale bars: c=100 μm, d, f–h=20 μm, e, i, j=10 μm, k=5 μm

Figure 2 – Phylogram generated from the best scoring of the RAxML tree based on combined LSU, ITS, ACT, BTUB and TEF1-α sequence dataset to indicate the taxa in Thyronectria. Forty-one strains are included in the combined analyses which comprise a total of 4040 characters. Hydropisphaera fungicola (CBS 122304) and Verrucostoma freycinetiae (TPP-h 523) are selected as the outgroup taxa. The best RAxML tree with a final likelihood value of − 28737.934247 is presented. RAxML analysis yielded 1441 distinct alignment patterns and 21.81% of undetermined characters or gaps. Estimated base frequencies were as follows: A=0.218868, C=0.290291, G=0.260083, T=0.230759, with substitution rates AC=0.91049, AG=2.312893, AT=1.471029, CG=0.955498, CT=5.294875, GT=1.000000; gamma distribution shape parameter alpha=0.629127. Bootstrap support values for maximum likelihood (MLBS) equal to or greater than 70% is given above the nodes. Newly generated sequences are in blue