Anthracothecium cellulosum (C.Knight) Müll.Arg.
Verrucaria cellulosa Knight, Trans. Linn. Soc. Lond. 23: 100 (1860).
Thallus spreading in irregular patches, 1-2 cm diam., effuse or lacking, olive-green to pale brownish-grey, rather varnish-like in parts, without a prothallus, corticolous. Pseudothecia simple, black, solitary, scattered, ± immersed at first, becoming subglobose, shining, epruinose, minute, 0.05-0.2 mm diam. Ascospores 8 per ascus, oblong-ellipsoid, biseriate, muriform, colourless to pale yellow-brownish 35-52 × 8-13 µm.
N: ?Auckland. Known only from the type collection. Lectotype: New Zealand. Sine loco (prob. Auckland). Charles Knight 323, BM!
Endemic
The type specimen (BM) is on smooth bark, possibly supplejack from deep shade, a probable substrate for this taxon.