Arthonia nigrocincta C.Knight & Mitt.
Lectotype: New Zealand. Sine loco. Charles Knight 292, 1858, BM!
Thallus pale greyish-yellowish to dull whitish, smooth, shining to roughened-cracked in mosaics to 5 cm diam., delimited by a thin black line. Ascocarps irregular, sessile or ± innate, round to oblong, bent or curved, one end longer, matt, blackish brown. Ascospores obovate, 4-septate, end cell largest.
N: Known only from the type collection ?Auckland.
Endemic
