Published online by Cambridge University Press: 28 March 2007
Labyrintha Malcolm, Elix & Owe-Larsson, a new genus in the Porpidiaceae, is described. It is based on the crustose taxon L. implexa Malcolm, Elix & Owe-Larsson, a saxicolous species from acidic rocks in alpine and subalpine areas in New Zealand. Labyrintha is distinguished from closely related genera by a combination of characters: cephalodia, immersed apothecia, large, simple ascospores (60–70 × 30–35 μm), halonate when young and dark-pigmented when mature, fusiform conidia, no cortex, no thallus chemistry, densely packed anticlinal hyphae, and a previously undescribed thallus anatomy in which the photobiont is arranged in anastomosing vertical sheets.