Physcia tenuisecta Zahlbr.
Holotype: New Zealand. North Auckland. Mahurangi River on Avicennia. L.B. Moore ZA 3580, W!
Thallus lobate, rosette-forming, to 2.5 cm diam., closely attached, corticolous. Lobes rather crowded, slender, laciniate, 0.2-0.25 mm wide, stellate-radiating, linear, irregularly or subdichotomously branching, margins uneven, swollen in parts, without cilia, apices rounded or slightly notched, crowded centrally often ± lobulate. Upper surface smooth, ± plane, matt or shining, greenish to brownish-white. Lower surface brownish-black, densely rhizinate. Rhizines brown or black, slightly thickened, simple or branched. Apothecia sessile, constricted at base, scattered, to 0.8 mm diam., disc black or brownish, epruinose, plane, margins thick, entire, concolorous with thallus. Ascospores biseriate, oblongellipsoid, straight or curved, 16-21 × 8-9 µm. Chemistry: Cortex and medulla K+ yellow. Atranorin and zeorin.
N: North Auckland (Three Kings Is to Rangitoto). Epiphytic on coastal trees and shrubs (Avicennia, Cordyline, Metrosideros).
Endemic
