Phaeostagonospora A.W. Ramaley, Mycotaxon 61: 351 (1997).
Index Fungorum number: IF 27759; Facesoffungi number: FoF 00267, 1 morphological species (Species Fungorum 2022), no molecular data available.
Saprobic on Nolina erumpens (Torr.) S. Wats. Sexual morph: reported as Phaeosphaeriopsis. Asexual morph: Conidiomata pycnidial, scattered, solitary, immersed or subepidermal, uniloculate, elongated to globose, flattened at the apex against the host epidermis, with small papilla penetrating the host epidermis. Conidiomata walls thick, composed of 3–6 layers of brown-walled cells, with 1–2 hyaline interior layers, abundant light brown hyphae from walls associated with host substrate. Conidiophores reduced to conidiogenous cells. Conidiogenous cells holoblastic, discrete, doliiform, ampulliform or irregular in shape, hyaline, smooth-walled, lining inner cavity of conidiomata. Macroconidia phragmosporous, ellipsoidal to cylindrical, with rounded ends, brown, 1–3-septate, rough-walled, foveolate. Microconidia globose or ellipsoidal, hyaline, smooth-walled, forming on the conidiomatal wall near the ostiole (adapted from Ramaley 1997).
Type species: Paraphaeosphaeria nolinae A.W. Ramaley
Notes: Phaeostagonospora is characterised by pycnidial, scattered, solitary, immersed or subepidermal, uniloculate conidiomata, holoblastic, discrete, doliiform, ampulliform conidiogenous cells, phragmosporous, ellipsoidal to cylindrical brown, 1–3-septate macroconidia and globose or ellipsoidal, hyaline, smooth-walled microconidia. Câmara et al. (2003) mentioned that Phaeostagonospora was the asexual morph of Phaeosphaeriopsis. This observation was based on co-occurrence on the host hence the sexual and asexual connection was not confirmed (Ramaley 1997; Câmara et al. 2001). Thambugala et al. (2014) epitypified Phaeosphaeriopsis glaucopunctata and described the asexual morph from cultures. The asexual morph of Phaeosphaeriopsis can be distinguished from Phaeostagonospora in that the former has aseptate, smaller, and verruculose conidia while the latter is characterised by septate conidia and larger microconidia (Ramaley 1997; Thambugala et al. 2014). Phaeostagonospora is a distinct genus in Phaeosphaeriaceae but the relationship between Phaeostagonospora and Phaeosphaeriopsis needs confirmation.