Swinscowia S.H. Jiang, Lücking & Sérus. gen. nov.
MycoBank number: MB 836396; Index Fungorum number: IF 836396; Facesoffungi number: FoF 08890;
34 morphologically delimited species (this paper); molecular data available for one species (Nelsen et al. 2011a).
Lichenized on bark and rocks in terrestrial, temperate- subalpine to tropical habitats. Thallus usually ecorticate, whitish to brownish. Photobiont Trentepohlia. Sexual morph: Ascomata perithecia, usually dispersed but often dense, immersed-erumpent to prominent, usually black or covered by thallus layer, rarely pale, lens-shaped to wartshaped, usually carbonaceous, rarely with pale to brownish walls, ostiolate. Involucrellum usually present and carbonized, rarely reduced or pale. Excipulum prosoplectenchymatous, pale to brown or blackish. Hamathecium comprising 0.5–0.7 µm wide paraphyses, hyaline, flexuose, typically branched and sometimes somewhat anastomosing. Asci usually 8-spored, rarely as little as 2-spored, bitunicate, fissitunicate, cylindrical to narrowly obclavate, shortly pedicellate, with narrow, non–amyloid ocular chamber. Ascospores irregularly arranged to uni- or biseriate, fusiform to ellipsoid or bacillar, hyaline, 1-septate to mostly 3–7-septate to (sub-)muriform, with thin eusepta and rectangular lumina, smooth-walled, often constricted (and sometimes breaking apart) at the septa. Asexual morph: Pycnidia common, immersed to erumpent, usually visible as black dots. Conidia typically acrogenous, either macro- or microconidia; macro- conidia (1–)3–7(–11)-septate to more rarely submuriform, oblong-ellipsoid to bacillar, with variably shaped gelatinous appendages, hyaline; microconidia aseptate, ellipsoid to fusiform, small, hyaline.
Chemistry: No secondary substances known.
Type species: Swinscowia jamesii (Swinscow) S.H. Jiang, Lücking & Sérus. (see below).
Notes: – This new genus, named after the British lichenologist Thomas Douglas Victor Swinscow, who first described the type species, Geissleria jamesii (Swinscow 1967), is here introduced for non-foliicolous species centered around Strigula jamesii. Since the latter is the only species sequenced so far, it is unclear whether the taxa included here all form a monophyletic group. Given the phylogenetic and morpho-anatomical differentiation in the foliicolous line- ages, likely more than one genus may be recognized for the non-foliicolous species here placed in Swinscowia. In their treatment of European taxa, Roux and Sérusiaux (2004) already arranged the non-foliicolous species into two major groups, their Strigula affinis-tagananae-calcarea group (“ensemble 2”) corresponding to Swinscowia.