Fungalpedia – Note 316, Kastanostachys
Kastanostachys L. Lombard & Crous
Citation when using this entry: Perera et al. 2024 (in prep) – Fungalpedia, genera described in 2016.
Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig. 1
Classification: Stachybotryaceae, Hypocreales, Hypocreomycetidae, Sordariomycetes, Pezizomycotina, Ascomycota, Fungi
Considering the ascomatal morphology Réblová (1998) transferred Melanomma aterrima to Chaetosphaeria (Chaetosphaeriaceae) by providing new name combination, Chaetosphaeria aterrima. Later, Lombard et al. (2016) established the monotypic genus Kastanostachys in Stachybotryaceae for Chaetosphaeria aterrima, based on the phylogenetic inference of cmdA, ITS, rpb2 and tub2 markers. Kastanostachys is characterized by perithecial ascomata that are superficial on the substrate with a slightly immersed base and arranged solitarily or in groups of 2–4. Ascomata are globose to subglobose, black, glabrous, ostiolate, papillate. They possess conidiophores comparable to those emerging from substrates. The peridium consists of two layers with prismatica texture. The outer layer consists of melanised cells with thick walls, whereas inner layer comprises of hyaline, compressed and elongated cells. Asci are unitunicate, 8-spored and shortly stipitate. They are cylindrical and truncate to broadly rounded at the apex with an apical ring. The paraphyses are numerous, branched, anastomosed, septate and hyaline. Ascospores are fusiform, 1-septate, not or slightly constricted at the septum, hyaline with smooth walls, enclosed in a hyaline sheath that disintegrates with age; each cell contains 1–2 oil drops. The asexual morph of the genus is characterized by macronematous conidiophores that are erect, septate, and unbranched, with one to occasionally three percurrent proliferations. The conidiophores have thick walls, are dark brown and become paler at the apex and enlarge to form a more or less distinct vesicle. The vesicles are pale brown to subhyaline, clavate, smooth-walled, and produce phialides in the upper part. Phialides are aseptate, straight or curved, cylindrical to clavate, and hyaline, with indistinct collarettes. They form conidia in their slimy heads. Conidia are hyaline, smooth-walled, and ellipsoidal, with a slightly truncate base (Réblová 1998; Lombard et al. 2016). Kastanostachys aterrima was isolated from decayed wood (Réblová 1998; Lombard et al. 2016).
Type species: Kastanostachys aterrima (Fuckel) L. Lombard & Crous
Other accepted species: This genus is monotypic.
Figure 1 – Kastanostachys aterrima (a, b: holotype of Melanomma aterrima; c–f: CBS 101310, ex-epitype of Kastanostachys aterrima). a Ascus with paraphyses and ascospores. b Ascospores. c Conidiophores. d, e Conidiogenous cells. f Conidia. Scale bars: a, b = 10 μm, c = 50 μm, d–f = 10 μm. Redrawn from Réblová (1998) and Lombard et al. (2016)
References
Entry by
Rekhani Hansika Perera, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand.
(Edited by Kevin D. Hyde, Samaneh Chaharmiri-Dokhaharani, & Achala R. Rathnayaka)
Published online 27 August 2024