Fungalpedia – Note 600, Asterina
Asterina Lév.
Citation when using this data: D. S. Marasinghe et al. 2023 (in prep.) – Fungalpedia, Ascomycota.
Index Fungorum, Facesoffungi, MycoBank, GenBank.
Classification: Asterinaceae, Asterinales, Dothideomycetidae, Dothideomycetes, Pezizomycotina, Ascomycota, Fungi
Epiphytic and biotrophic on leaves appearing as blackened web-like areas. Superficial hyphae dark brown to brown, septate, comprising appressoria which penetrate host tissues and develop haustoria in mesophyll cells. Sexual morphs: Thyriothecia superficial, solitary to gregarious, flattened, membranous, dark brown to black, circular, easily detached from the host, opening by radiating star-like fissures, fibrous at the margin. Upper wall comprises dark brown to brown, poorly developed base, radially arranged cells of textura prismatica branching and attaching to the surface mycelia. Hamathecium lacking pseudoparaphyses or with interascal tissue. Asci 8-spored, bitunicate, fissitunicate, globose or broadly saccate, usually sessile or with a short indistinct pedicel, with a thickened hyaline apical region, distinct ocular chamber lacking. Ascospores 2–5-seriate or fasciculate, conglobate to ellipsoidal, occasionally cylindrical, hyaline or brown, mostly 1-septum, mostly brown when mature, walls smooth or roughened. Asexual morphs: Coelomycetous. Superficial hyphae dark brown to brown, septate, with appressoria. Pycnothyria flattened, superficial, dimidiate, orbicular, stellately dehisced at the centre and similar in morphology of sexual morph. Conidiophores branched or unbranched, hyaline or brown. Conidiogenous cells monoblastic or percurrent, hyaline or brown. Conidia brown, ovate, pyriform, angular, or wall straight to sinuate, smooth-walled (Hofmann 2010; Hyde et al. 2013; Hongsanan et al. 2014a).
Notes: Léveillé (1845) introduced Asterina which is the type genus of Asterinaceae. Species of Asterina are characterized by circular thyriothecia with stellate dehiscence, lateral appressoria, globose asci, and dark brown, 1-sep- tum ascospores (Hongsanan et al. 2020a). Many historical mycologists described Asterina species before 1910 to accommodate species with dimidiate and globose thyriothecia (Hongsanan et al. 2014a). Hofmann (2010) reported numerous taxa in Panama while Housagoudar (2012) monographed Asterina in India. Hofmann (2010) provided the first sequence data for this genus and confirmed the placement in Dothideomycetes. Species of this genus are obligate plant parasites distributed in tropical and subtropical regions worldwide (Hongsanan et al. 2014a). The asexual morph of Asterina was recorded as Asterostomella and is characterized by superficial dark brown to brown, orbicular pycnothyria, appressoriate superficial hyphae with brown, ovoid, aseptate conidia (Fig. 1). Hyde et al. (2020a) provided the first molecular data for Asterostomella grewiae (MFLU 13-0629) and it clusters together with other Asterina spp. Therefore, we suggest Asterostomella as the asexual morph of Asterina under the rule of one name one fungus until in-depth studies. The recommended genes to resolve Asterina species are LSU, ITS and SSU.
Type species: Asterina melastomatis Lév., Annls Sci. Nat., Bot., sér. 3 3: 59 (1845).
Other accepted species: Species Fungorum – search Asterina.
Figure 1 – Asterina paraguayensis. a Host leaves. b Colonies of host leaves. c Orbicular pycnothyria with surface mycelia. d Section through pycnothyrium. e Haustoria forming inside the host tissue. f Conidia. Scale bar not mentioned. Redrawn from Arnaud (1918)
References
Arnaud G 1918 – Les Astérinées. Annales de l’école Nationale d’agriculture de Montpellier 16:1.
Hofmann TA 2010 – PhD thesis. The faculty of biological sciences at the J.W. Goethe-University Frankfurt am Main, Germany,p 408.
Hongsanan S, Li YM, Liu JK et al 2014a – Revision of genera in Asterinales. Fungal Divers 68:1–68.
Hyde KD, Jones EBG, Liu JK et al 2013 – Families of Dothideomycetes. Fungal Divers 63:1–313.
Léveillé JH 1845 – Champignons exotiques. Ann Sci Nat Ser 3(3):38–71.
Entry by
Diana Sandamali Marasinghe, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand School of Science, Mae Fah Luang University, Chiang Rai, 57100, Thailand, Mushroom Research Foundation, 128 M.3 Ban Pa Deng T. Pa Pae, A. Mae Taeng, Chiang Mai, 50150, Thailand
Published online 29 August 2023