Dactylidina shoemakeri
Dactylidina shoemakeri Wanas., Camporesi, E.B.G. Jones & K.D. Hyde, in Wanasinghe et al., Fungal Diversity: 10.1007/s13225-018-0395-7, [109] (2018)
Index Fungorum number: IF 554175; Facesofungi number: FoF 04017
Etymology: In honour of R.A. Shoemaker, for his immense contribution to mycology.
Holotype: MFLU 16-0202.
Saprobic on Poa sp. Sexual morph: Ascomata 140–180 μm high, 150–180 μm diam. (x̄ = 157.4 × 165.4 μm, n= 5), immersed to erumpent, solitary, scattered, globose or subglobose, dark brown to black, coriaceous, ostiolate. Ostiole papillate, eccentric, blackish-brown, smooth, comprising brown cells. Peridium 5–15 μm wide, comprising, heavily pigmented, thin-walled, brown to dark brown cells of textura angularis. Hamathecium comprising numerous, 1.5–2.5 μm wide, filamentous, branched, septate, pseudoparaphyses. Asci 90–105 × 18–23 μm (x̄ = 98.6 × 21 μm, n = 20), 8-spored, bitunicate, fissitunicate, clavate, short pedicellate, thick-walled at the apex, with minute ocular chamber. Ascospores 23–27 × 9–11 μm (x̄ = 24.8 × 9.8 μm, n = 30), overlapping 1–2-seriate, ellipsoidal to subfusiform, muriform, upper part wider than the lower part, 4–5-transversely septate, with 1–2 vertical septa, constricted at the central septum, initially hyaline, becoming yellowish-brown at maturity, ends remaining lighter and cone-shaped, with rounded ends, surrounded by a thick mucilaginous sheath. Asexual morph: Undetermined.
Material examined: ITALY, Trento, Marilleva 1400, on dead aerial stems of Poa sp. (Poaceae), 2 August 2013, Erio Camporesi IT 1932 (MFLU 16-0202, holotype); ex-type living culture, MFLUCC 14-0963.
GenBank Numbers: ITS: MG828887, LSU: MG829003, SSU: MG829114, TEF: MG829200.
Notes: Dactylidina dactylidis and D. shoemakeri together in a monophyletic clade in Phaeosphaeriaceae with strong bootstrap support. They are similar in ascomata characters (immersed to erumpent, solitary, scattered, globose or subglobose, dark brown to black, coriaceous, ostiolate, thin-walled) and with muriform ascospores. However, Dactylidina dactylidis differs from D. shoemaker in having mostly cylindric-clavate asci and ascospores with 1-longitidinal septum, while D. shoemakeri has mostly clavate asci with ascospores, having 1–2-longitudinal septa. To further support the establishment of the new taxon as proposed by Jeewon and Hyde (2016), we examined the nucleotide differences within the ITS regions (ITS1-5.8S-ITS2) gene region. Comparison of the 544 nucleotides across the ITS regions reveals 11 bp (2%) differences between Dactylidina dactylidis and D. shoemakeri.
Figure x. Dactylidina shoemakeri (MFLU 16-0202, holotype). a, b Ascomata on host substrate. c Section of ascoma. d Peridium. e Pseudoparaphyses. f–i Asci. j–l Ascospores (note the mucilaginous sheath stained with Indian ink in l). Scale bars: a = 1 mm, b = 200 μm, c = 100 μm, d, j–l = 10 μm, e = 5 μm, f–i = 20 μm.
References:
Jeewon R, Hyde KD (2016) Establishing species boundaries and new taxa among fungi: recommendations to resolve taxonomic ambiguities. Mycosphere 7, 1669–1677.
Wanasinghe DN, Phukhamsakda C, Hyde KD, Jeewon R et al. 2018 – Fungal diversity notes 709–839: taxonomic and phylogenetic contributions to fungal taxa with an emphasis on fungi on Rosaceae. Fungal diversity 89, 1–236.