Trichoglossum beninense De Kesel, Hustad, A.N. Mill., Fedosova & V. Kučera, sp. nov.
Index Fungorum number: IF 557835; MycoBank number: MB 557835; Facesoffungi number: FoF 13917; Fig. 1
Etymology – epithet refers to Benin, West-African country where the type was found.
Fruiting bodies develop on sandy soil with some humus, usually under Uapaca guineensis Müll.Arg., U. togoensis Pax (Phyllanthaceae), Berlinia grandiflora Hutch. & Dalziela (Caesalpiniaceae), and Isoberlinia doka Craib & Stapf (Caesalpiniaceae). Sexual morph: Ascomata 20–45 mm high, capitate, stipitate, dry, hairy, black, locally with a greenish hue. Ascigerous part capitate or spoon-shaped, 1/5–1/3 of the total ascoma length, black, compressed, fresh with greyish-white context becoming slightly orange in longitudinal section, sharply delimited from the stipe, surface smooth and appears hairy due to discharged ascospores. Stipe 14–37×1–1.5 mm, cylindrical, terete or oval in cross section, slender, hirsute, with dark brown to black setae, when fresh blackish-orange in longitudinal section. Hymenial layer (230–)240–250(–260) μm thick. Stipe surface formed by inflated cells (13–40 × 5–12 µm) or by short chains (2–3 cells where the last cell is the most inflated) and between them setae of 120–180×5–11 µm (rarely up to 250 µm long), stipe base covered by dark ground mycelium, in young ascocarps sometimes ascending the stipe, composed of thin, black hyphae (33–62 × 2–2.5 µm). Hymenial setae rare, blackish-brown, tapered at the apex usually with protuberance (6–19 µm) in the basal part, thick-walled, (100–)125–218(–280) × (5–)5.5–7.5(–8) µm, (5–)20–30(–40) µm protruding above hymenium or (5–)25–40(–100) µm below surface of the hymenium, density above hymenium (0–)0.5(–2) pieces per 500 μm2 , density in hymenium (0–)1–2(–3) pieces per 500 μm2. Paraphyses longer than asci, straight, sparsely septate, 2–4 µm wide in the middle part, hyaline at basal part, pale brown at the apex. Apical cells of paraphyses curved to circinate, sometimes club-shaped, slightly inflated, seldom branched (35–)47–73(–84)×(3)4.2–6.3(–8.5) µm, pale brown. Asci cylindrical-clavate, narrowed at the base, (201–)213–245(–268)×(15–)16–19(–25) µm, Q=(8.8–)9.8–13(–14.8), unitunicate, inoperculate, 8-spored, with euamyloid ascoapical apparatus and slightly amyloid wall in Melzer and IKI, arising from croziers. Ascospores elongate, subfusiform to fusiform, narrowed to the ends, sometimes slightly curved, initially 5–7-septate and (71–)122–166(–180)×(4–)4.9–6.1(–6.9)–6 µm, Q=(13.5–)22.3–30.5(–35.4) and when matured only 15-septated and (112–)139–165(–180)×(4.5–)5.1–6. 1(–6.9) µm, Q =(17.6–)24.2–30.8(–35.4), brown, smooth (all measurements of microscopic characters refer to material observed in 5% KOH). Asexual morph: Undetermined.
Material examined – Benin, Atakora Province, Kota, N10° 12.770′ E1° 26.750′, alt. 512 m, steep and rocky gallery forest with Uapaca guineensis (Phyllanthaceae) on soil with humus, 15 September 2001, A. De Kesel, ADK 3172 (BR5020149821538 holotype deposited at BR); ibid., 10° 12.680′ N 1° 26.723′ E, alt. 518 m, forest gallery with U. guineensis (Phyllanthaceae) and Berlinia grandiflora (Caesalpiniaceae), on soil, near stream and waterfall, 29 August 1997, A. De Kesel, ADK 2015 (BR5020074861746); Togo, Centrale Province, Fazao National Park, 08° 41.133′ N 0° 45.623′ E, alt. 625 m, rivulet associated woodland, on a slope, dominated by U. togoensis (Phyllanthaceae) and Isoberlinia doka (Caesalpiniaceae), on soil of the vertical bank of the rivulet, 19 July 2007, A. De Kesel, ADK 4439 (BR5020163771352).
GenBank numbers – ITS: OP355329, OP355330, LSU: OP355337
Notes – The ITS and LSU sequence data of our collection give Trichoglossum species as the closest matches in NCBI. The genus Trichoglossum is characterized by the hirsute look of the fertile part of ascomata. In our material the setae, responsible for this hirsute look, are relatively short and distributed infrequently in the hymenium and stipe. The 5–7-septate ascospores are clearly shorter (80–125 µm) than those with 15 septa (139–165 µm). The other Trichoglossum species with eight-spored asci and 15-septated ascospores are T. cheliense F.L. Tai, T. gracile Pat., T. hirsutum (Pers.) Boud., T. jejuense S.H. Lee, T. longisporum F. L. Tai, T. persoonii F.L. Tai, T. septatum Ekanayaka, Q. Zhao & K.D. Hyde, T. sinicum F.L. Tai, T. variabile (E.J. Durand) Nannf., and T. yunnanense L.F. Tai (Ekanayaka et al. 2017; Prabhugaonkar and Pratibha 2017; Lee et al. 2021; Chakraborty et al. 2022). Our material differs from these species in having very sparsely distributed setae in the hymenium and short setae on the stipe surface. The orange coloring in the longitudinal section is also noteworthy. The field surveys indicate that this species only occurs in steep forest galleries with relatively cool and wet conditions during the long dry season (October–March). Ascomata are produced very late in the second half of the rainy season (July–September). It seems to prefer deep shade and develops on sandy soil with some humus, always under ectomycorrhizal trees Berlinia grandiflora, Isoberlinia doka, Uapaca guineensis and U. togoensis. Edibility is unknown. Phylogenetic evidences reveal that our collections form a distinct clade between several undescribed Trichoglossum species with ML/BI=100%/1.00 statistical supports. Therefore, we introduce our material as T. beninense sp. nov. This species is only known from Benin and Togo in Africa (Fig. 2).
Figure 1 – Trichoglossum beninense (BR5020149821538, holotype). a Ascospores. b Paraphyses. c Setae. d Hymenium. e Asci showing euamyloid reaction of the ascoapical apparatus. f Elements of the stipe surface. g Fresh ascomata. h Habitat of T. beninense. (a–d,
f in 5% KOH, e in IKI). Scale bars: a–f=10 µm, g=1 cm
Figure 2 – Phylogram generated from maximum likelihood analysis based on ITS sequence data for Trichoglossum and several closely related genera in Geoglossaceae. Thirty-two specimens are included in the analyses. The matrix comprised aligned 703 characters, which was reduced to 535 characters including gaps after elimination of 168 characters by TrimAl v.1.2b. The tree is rooted with Geoglossum glabrum (ILLS 61038 and ILLS 72358). The best-fit AICc-selected models of evolution is TVM+I+G. The best scoring RAxML tree has a final likelihood value of − 5633.290401. The matrix had 352 distinct alignment patterns with 5.13% undetermined characters and gaps. Estimated base frequencies were as follows: A=0.237638, C=0.234066, G=0.231049, T=0.297247; substitution rates AC=0.994448, AG=3.586652, AT=1.129458, CG=0.458687, CT=3.969106, GT=1.0; gamma distribution shape parameter α=0.808425. To remove the prestationary posterior probability distribution burn-in of 10% (ESS=3621.7) was estimated with Tracer to be sufficient. Alignments and phylogenies were deposited in TreeBASE (http://treebase.org) under the submission ID 29628. Type specimens are in bold and newly generated sequences are in blue. Bootstrap support for ML equal to or greater than 80% and BI equal to or greater than 0.95 are given above the nodes