Scutula Tul.
Type : * Scutula wallrothii Tul., typ. cons. [= * Scutula epiblastematica (Wallr.) Rehm (= * Peziza epiblastematica Wallr.)]
Description : Lichenicolous endokapylic or epikapylic, sometimes damaging host tissue. Ascomata apothecia, sessile, constricted at base, rounded, scattered to clustered; disc plane to convex, cream to pale-brown, dark-brown or black, matt to glossy; margins distinct pale- to dark-brown or black. Exciple prominent, of parallel, radiating, branched, anastomosing, conglutinate hyphae, outer parts colourless, pale-brown to dark reddish brown, apically with an unevenly distributed, granular, greenish brown to greenish black pigment; inner parts colourless, greenish brown to red-brown. Hypothecium of loosely intricated hyphae, colourless to brown. Subhymenium colourless. Hymenium colourless, to pale-brownish or greenish, black in upper parts, I+ pale-blue to blue. Hamathecium of paraphyses, septate, very sparingly branched and anastomosing; apical cells thickened to clavate. Epithecium discontinuous, unevenly granular, greenish brown to greenish black. Asci 6–8-spored, Scutula -type (with amyloid tholus and diffuse non-amyloid axial body). Ascospores (0–)1(–3)-septate, narrowly to broadly ellipsoidal, apices usually attenuated, sometimes with oil droplets, thin-walled, smooth, colourless. Conidiomata pycnidia, containing microconidia, globose, subimmersed to sessile; wall apically colourless, red to dark-brown, blackish brown or greenish black, basally colourless to pale-brown. Conidiophores short, of 2–5 cells, sparingly branched, cells cylindrical to short-rectangular, colourless. Conidiogenous cells enteroblastic, phialidic, lageniform to cylindrical; conidia predominantly acrogenous, occasionally pleurogenous. Microconidia simple, bacillar to filiform, sometimes curved, colourless. Conidia containing mesoconidia of Libertiella -type. Conidiomata containing macroconidia of Karsteniomyces -type.
Mesconidial state: Libertiella Speg & Roum., 1880.
Conidiomata pycnidia, globose, subimmersed to sessile, on upper and lower surfaces of host thallus; wall apically colourless or pale- to dark-brown, basally colourless to pale brownish, ±pseudoparenchymatous, inner cells elongate, periclinal. Conidiophores short, of 1–2 cells, cells cylindrical to short-rectangular, colourless. Conidiogenous cells enteroblastic, phialidic, lageniform to cylindrical. Conidia rising acrogenously or occasionally pleurogenously, simple, bacillar to falcate, often irregular, colourless,
Macroconidial state: Karsteniomyces D. Hawksw. 1980.
Conidiomata pycnidia, globose, sessile; wall apically colourless, red to dark-brown, blackish brown or greenish brown, basally colourless to pale-brown to red-brown, ±pseudoparenchymatous. Conidiophores short, of 1–4 cells, not or very sparingly branched; cells cylindrical to short-rectangular, colourless. Conidiogenous cells holoblastic, cylindrical. Conidia arising acrogenously, simple to 1-septate, oblong-cylindrical to bacillar, somewhat irregular, colourless.
Scutula is a genus of c. 10 species of lichenicolous fungi (Vainio 1933; Alstrup & Hawksworth 1990; Rambold & Triebel 1992; Jørgensen & Santesson 1993; Triebel et al. 1997; Etayo 2002; Triebel & Kainz 2004b) formerly included in the family Micareaceae (Lawrey & Diederich 2003; Eriksson et al. 2004; Pennycook & Galloway 2004), but now accommodated in Pilocarpaceae (Andersen & Ekman 2005; Eriksson 2005). Scutula was widely used for lichenicolous taxa having colourless, 1-septate ascospores and apothecial ascomata; however, this resulted in an artificial genus concept. Currently, Scutula s. str. is characterised by the following characters: lichenicolous thallus, crustose or endosubstratic; ascomata apothecia, lecideine; asci with a fuzzy axial structure in the apical tholus (an intermediate structure between the amyloid tube of "Micarea -type" ascus and the axial body surrounded by an amyloid edge of "Biatora -type" ascus); mainly 1-septate, smooth-walled ascospores; three types of conidia occur: microconida, mesoconidia of Libertiella -type and macroconidia of Karsteniomyces -type. Species occur on Cladonia, Leptogium, Lobaria, Mycobilimbia, Nephroma, Peltigera, Solorina and Stereocaulon as hosts, with most taxa being associated with Peltigera (Rambold & Triebel 1992; Triebel et al. 1997). One species is known from New Zealand.
