Opegrapha murina
Lectotype selected here: New Zealand. Sine loco [probably Wellington], Charles Knight s.n. – M 0035879. Isolectotype – M 0035788.
Description : Thallus thin, roughened–scurfy to evanescent, whitish to greyish white, spreading in irregular patches 1–2(–4) cm diam., not delimited by a marginal prothallus. Apothecia coal-black, shining, sessile, widely scattered, solitary, 0.1–1(–1.2) mm long and 0.05 mm wide, linear or subarcuate, never branched or flexuous, lips prominent, separated by a narrow slit. Hamathecium of richly branched and anastomosing paraphysoids. Asci clavate, 8-spored, (55–)60–65 × 16–20 μm. Ascospores fusiform, colourless, 3-septate, 25–28.5 × 6.5–8.5 μm, with a distinct perispore 1–1.5 μm thick.
Chemistry : TLC−, all reactions negative.
Endemic
Opegrapha murina is characterised by: the corticolous habit; the thin grey thallus; very small, scattered, coal-black apothecia; 8-spored asci; and colourless, fusiform, 3-septate ascospores, 25–28.5 × 6.5–8.5 μm, with a distinct perispore 1–1.5 μm thick.
