Flora of New Zealand Series

Thallus crustose, uniform, horny, verrucose or effigurate, bright yellow (calycin and pulvinic dilactone) not turning purple on addition of KOH. Photobiont green, Protococcus. Lower cortex absent. Apothecia sessile, circular, yellow. Ascospores 8 to many per ascus, colourless, elongate to ellipsoid, simple to 1-septate, walls and septum thin.

Candelariella is a cosmopolitan genus of c. 40 species included in the family Candelariaceae. The abundant production of pulvinic acid derivatives gives the species their characteristic yellow colour. Three species are known in New Zealand. Monographs of the genus are those of Hakulinen [ Annls Bot. Soc. Zool.-Bot. fenn. Vanamo 27 (3): 1-127 (1954)], and Thomson [ Revta Fac. Cienc. Univ. Lisb. sér. 2, 17 (2): 747-759 (1973)].