ABSTRACT: The new species Xanthoria tenuiloba (Teloschistaceae, lichenized Ascomycotina) is described from Baja California, Mexico. It is characterized by a mostly greyish, subfruticose-fruticose thallus with very narrow and slender, nodulose lobes, and abundant blastidia. Apothecia and pycnidia are always orange pigmented, and conidia are ellipsoid. It grows on dry twigs and occasionally on rock in near-coastal scrub vegetation.

KEYWORDS: Flora of North America, lichenized ascomycetes, Teloschistaceae, HPTLC

NOMENCLATURAL NOVELTIES:
Xanthoria tenuiloba L. Lindblom, p. 376