You are here
Taxon Pages
Byssoloma spinulosum Sérus.
Nomenclature
-
Family: PilocarpaceaeGenus: Byssoloma
Media
SUMMARY
Mycobank MB 517740
Thallus mostly developed along margins and scars of living leaves, over 1–1.5 cm in diam, usually continuous near the margins (not developing on the under surface of the leaves, not even in a non-lichenized stade) but typically patchy, patches irregular in shape and size, whitish to very pale bluish, seemingly cottony at high magnification, withish prothallus sometimes seen between the patches (hyphae distinct at high magnification). Apothecia present or not, rounded, (0.3–)0.4–0.5(–0.6) mm in diam. (incl. the margin), with a pale yellowish to whitish margin, typically byssoid, especially in young apothecia, getting thinner when old but never excluded, disc first slightly concave and eventually flat, bluish black. Excipulum made of densely interwoven, almost cylindrical hyphae, without constrictions, inspersed with minute, pale orange brown crystals (not disappearing in K). Hypothecium and apothecia basal center brown to dark brown, K+ dark brown or usually purple brown to bluish black. Asci clavate, 40–45 x 5–10 µm, of the Byssoloma-type. Paraphyses simple or slightly branched, not broadened at apices. Ascospores 8/ascus, ellipsoid, 3-septate, with rounded ends and without constrictions at the septa, 12–15 x 3.5–4 µm, with a thin halo around them. Pycnidia mostly but not exclusively developed at the leaves margins (natural margins or along scars), typically in a single row at the margins, conical or almost so, with a short but nevertheless distinct beak, 0.15–0.2(–0.25) mm high, ca. 0.2 mm in diam., basis covered by the thallus (sometimes up to the ostiole margin) which can be slightly byssoid, upper part bluish grey to dark bluish, sometimes very pale, K+ pale bluish to aeruginose, a pale yellow orange glut of conidia sometimes present. Conidia numerous, rarely ellipsoid, usually enlarged at one end or typically pyriform, simple, colourless, 5–6 x 2–2.5 µm.