Flora of New Zealand Series

≡Lecanora pyrinus Ach., Lich. suec. prodr.: 52 (1799) ["1798"].

Description : Thallus epiphytic, rather thin and effuse, to moderately thick and areolate, often mealy-scabrid, pale-grey to dingy olive-grey, areolate, areolae minute, somewhat dispersed and discontinuous, especially at margins, continuous centrally and there plane to convex or bullate, without a prothallus. Apothecia 0.1–0.6 mm diam., scattered, numerous, subimmersed at first becoming lecanorine and sessile at maturity, disc plane, occasionally convex, brown to black, matt, somewhat scabrid. Thalline margin concolorous with thallus, well-developed, thin, entire, persistent. Parathecium 15– 20 μm wide, hyaline. Cortex indistinct, I−. Epithecium brown to dark-brown, unchanged in K, 5–10 μm thick. Hymenium colourless, 60–75 μm tall. Paraphyses 1.5–2 μm thick, apices to 4 μm diam. Hypothecium 40–60 μm thick. Asci Lecanora -type Ascospores Physconia -type, spore ontogeny type A, often slightly curved, with faint median thickenings, but without distinct apical thickenings when mature, pale- to dark-brown, smooth-walled, 12–15(–17) × 5–7 μm, torus sometimes evident, spore lumina with oil droplets (fresh specimens). Pycnidia immersed. Conidia bacillar, 4–6 × 1 μm.

Chemistry : TLC−, all reactions negative.

S: Marlborough (Kaikoura Peninsula), Canterbury (Waiau, Cheviot, Hanmer Springs, Banks Peninsula, Bankside Scenic Reserve), Otago (Lindis, Wanaka, Alexandra, Fruitlands, Mt Benger, Portobello), Southland (Five Rivers). Commonly the earliest coloniser on young twigs of introduced trees and shrubs (Mayrhofer et al. 1999: 190), and occurring on bark of both native (Cordyline australis, Discaria toumatou, Plagianthus regius, Sophora microphylla) and introduced trees (Acer negundo, A. pseudoplatanus, Fraxinus exelsior, Malus domestica, Populus alba, P. yunnanensis, Salix babylonica, Thymus vulgaris, Tilia cordata) in parks, gardens and roadsides. On eutrophicated bark of an isolated Sophora microphylla tree in grassland on Mt Benger, this species associates with Candelariella subdeflexa (Galloway & Hafellner 2002). Known also from Scandinavia, Europe, western North America, and SE Australia and Tasmania (Ropin & Mayrhofer 1993; Giralt & Mayrhofer 1995; Mayrhofer et al. 1999: 190; Mayrhofer & Moberg 2002b; McCarthy 2003c, 2006; Nimis & Martellos 2003; Sheard 2004).

Cosmopolitan

Illustrations : Ropin & Mayrhofer (1993: 785, fig. 14); Giralt & Mayrhofer (1995: 133, fig. 4C); Mayrhofer et al. (1999: 189, fig. 14); Boqueras (2000: 402, fig. 65 G); Edler (2002: 53, fig. 15); Nordic Lichen Flora Vol. 2 (2002: 107).

Rinodina pyrina is characterised by: the corticolous habit; the ascospores that lack the wall thickenings that characterise most species in this genus. At maturity the ascospores lack any apical thickenings and the median thickenings at the septum are so reduced as to appear of Buellia -type or Physconia -type.