Type. AUSTRALIA. New South Wales, Parramatta, W. Woolls (G, lectotype)

Description. Lichenized fungus.

Thallus crustose, areolate-soraliate/sorediate, bright yellow, composed of minute, flat areoles (0.07-0.2 mm diam.) that are often indistinct and dissolved into soredia 20-60 μm diam; photobiont chlorococcoid alga, cells 8.5-12.0 μm diam. Ascomata rare, small, lecaorine with thin margin; disk flat, dark yellow. Ascospores 8 per ascus, hyaline, simple, 11.0-17.5 x 3.5-7.0 μm; pycnidia not reported.

Chemistry. Spot tests negative; secondary metabolites include calycin and pulvinic acid.

Substrate and Habitat. On exposed bark of hardwood tree trunks and branches in mixed and hardwood forests, also in human-altered habitats.

Distribution. Australia, Europe, North America, east Asia (Japan); in North Carolina throughout.

Notes. This species was referred to C. reflexa in North America, but found to be identical with Australian specimens of C. xanthostigmoides, thus the latter name was applied (Lendemer & Wetsberg 2010). It has since been reported from Europe (Westberg & Clerc 2012) and Japan (Yalovchenko et al. 2022). It is a rather distinctive lichen on exposed trunks and branches, found common in urban environments as it is a nitrophilous lichen like Candelaria concolor, which it was found to be sympatric with (Perlmutter 2010).

Literature

Lendemer, J.C. & M. Westberg. (2010) Candelariella xanthostigmoides in North America. Opuscula Philolichenum 8: 75-81.

Müller, J. (1882). Lichenologische Beiträge XVI. Flora (Regensburg). 65: 483-490 (original description as Lecanora xanthostigmoides).

Perlmutter, G.B.  (2010) Bioassessing air pollution effects with epiphytic lichens in Raleigh, North Carolina, U.S.A. The Bryologist 113(1): 39-50.

Yakovchenko, L.S., E.A. Davydov & Y. Ohmura. (2022) Candelariella xanthostigmoides (Candelariaceae, Ascomycota) – a new lichen record to East Asia from Japan. Turczaninowia 25 (1): 124–128.