Pannoparmelia wilsonii (Räsänen) D.J.Galloway
Anzia wilsonii Räsänen, Annls Bot. Soc. Zool.-Bot. fenn. Vanamo 20 (3): 2 (1944).
Parmelia angustata var. isidiella Stirton., T.N.Z.I. 32: 81 (1900).
Thallus loosely attached, rosette-forming, 3-5(-8) cm diam., corticolous. Lobes convex, 0.5-1.0 mm wide, conspicuously constricted at branch points, branching dichotomous towards apices, ± densely imbricate centrally, margins entire, apices narrow, incised. Upper surface pale to bright yellow (usnic acid) smooth, glossy at apices, without soredia, maculae or pseudocyphellae, densely papillate-isidiate in older parts. Isidia simple, nodular, rather fragile, slightly expanded at tips, often densely crowded over whole upper surface and at lobe margins, rarely becoming coralloid-branched centrally. Lower cortex yellow, matt, smooth, visible at apices of lobes and between patches of hypothallus. Hypothallus spongy, compact, less than 1 mm thick, dark brown to black, moniliform. Rhizines common, black, simple or sparingly branched with an anchoring apical tuft. Apothecia rare, small, 3 mm diam., sessile. Margins distinctly isidiate, concolorous with thallus, disc smooth, imperforate, red-brown, thalline exciple wrinkled, isidiate, lacking tomentum. Pycnidia laminal, scattered, punctiform, black.
N: South Auckland (Te Aroha, Rotorua). S: Nelson (Lake Rotoiti, Maruia Valley), Canterbury (Nina Valley, near Lewis Pass). Epiphytic on Dracophyllum subulatum, Dacrycarpus dacrydioides and Leptospermum scoparium.
Australasian
P. wilsonii is a smaller and more delicate plant than P. angustata and appears to have a more restricted distribution in New Zealand. It is also much less variable. It is distinguished from Anzia jamesii, the isidiate Anzia present in New Zealand, in having usnic acid in the upper cortex (yellow), a moniliform hypothallus, a distinct lower cortex and narrower constricted lobes which lack an internal chondroid axis.
