Parmelia protosignifera
Description : Thallus loosely adnate, pale mineral-grey, becoming brownish and blackening with age, to 15 cm diam. Lobes sublinear, crowded, imbricate, 2–6(–10) mm wide, apices rounded, secondary lobes often building the thallus into a thick, pulvinate mat, ±lobulate with age centrally, lobules marginal, suberect. Upper surface shining at apices, becoming dull elsewhere, plane to wrinkled or faveolate, becoming extensively cracked with age, pseudocyphellate; without isidia or soredia. Pseudocyphellae effigurate, dense, often arranged in a reticulate pattern, appearing raised. Lower surface black centrally, brown at margins, densely rhizinate to margins. Rhizines simple, dichotomous or sparingly squarrosely branched, black, 0.8–1.2 mm long. Apothecia common, sessile to subpedicellate, to 8 mm diam., disc concave at first becoming undulate–distorted at maturity, pale-brown to dark-brown, margins thin, crenulate, deeply lacerate-incised; exciple pseudocyphellate. Ascospores ellipsoidal to broad-ellipsoidal, 11–15 × 8–9 μm. Pycnidia common, minute, punctiform. Conidia bifusiform, 6–7 × 1 μm.
Chemistry : Cortex: K+ yellow; medulla K+ pale yellow-brown, C−, Pd+ red-orange; containing atranorin, chloroatranorin and protocetraric acid.
S: Otago (Cave Hill near Dunedin). On rock; still very poorly collected in New Zealand. Known also from rock and soil in subalpine areas of New South Wales and Victoria (Elix & Johnston 1988a; Elix 1994m; McCarthy 2003c, 2006).
Australasian
Illustrations : Elix & Johnston (1988a: 494, fig. 3); Elix (1994m: 117, fig. 50B).
Parmelia protosignifera is characterised by: the prominent, effigurate pseudocyphellae forming a reticulate pattern; bifusiform conidia; and protocetraric acid in the medulla. It is distinguished from P. signifera by medullary chemistry (P. signifera has salazinic acid, K+ yellow→red).
