Flora of New Zealand Series

=Arthonia lirellaeformis C.Knight, Trans. N. Z. Inst. 15: 352 (1883).

Arthonia lirelliformis. Type: New Zealand. Sine loco [probably Wellington], Charles Knight – WELT.

Description : Thallus crustose, thin, grey-white or grey-blue, to lilac-grey, or grey-green, smooth, continuous to granular, powdery, sometimes delimited at margins by a thin, black prothalline line. Apothecia brownish, lirelliform, oblong or elongate, simple, or branched, heavily blue-grey-pruinose, easily distinguished from thallus. Hymenium colourless; epithecium brown-black. Asci broadly clavate. Ascospores pyriform to broadly cuneate-oblong, 4-septate, the end cell noticeably enlarged, 14–20 × 5–8 μm, colourless at first becoming red-brown or brownish at maturity.

Chemistry : K+ yellow; containing psoromic acid.

N: Auckland (Domain), Wellington. S: Otago (Cameron Flat near Makarora, Leith Valley, Mt Cargill). On dry, shaded bark of Nothofagus menziesii in humid, riverine habitats, and on dryish vertical scales of old Dacrydium cupressinum in humid forest. A species of dry, rough bark of mature trees in old-growth forest or forest remnants. Commonly associating with taxa of Calicales, Chrysothrix candelaris, Lepraria incana, Megalaria grossa, Opegrapha agelaeoides and Sagenidium molle. Known also from Europe, Scandinavia, North America, Tasmania (Coppins & James 1978; Nimis 1993; Santesson 1993; Esslinger & Egan 1995; Sundin & Tehler 1998; Kantvilas & Jarman 1999; Nimis & Martellos 2003; Santesson et al. 2004).

?Bipolar

Illustrations : Knight (1883: pl. XXXV, fig. 2 – as Arthonia lirellaeformis); Ozenda & Clauzade (1970: 222, fig. 172); Kantvilas & Jarman (1999: 29).

Arthonia cinereopruinosa is characterised by: the corticolous habit: the grey-white, grey-green to lilac-grey granular or powdery thallus delimited by a thin, black prothallus; lirellate, oblong or elongate, simple or branched, blue-grey-pruinose apothecia; pyriform to broadly cuneate-oblong, 4-septate ascospores, becoming red-brown at maturity, 14–20 × 5–8 μm; and psoromic acid (K+ yellow). Notes on type material are given in Coppins & James (1978: 185–187).