Flora of New Zealand Series

Type : Micarea prasina Fr.,  typ. cons.

Description : Flora (1985: 291).

Micarea is a cosmopolitan genus of more than 100 species (Andersen & Ekman 2004), placed in the family Micareaceae (Hafellner 1984; Eriksson et al. 2004; Pennycook & Galloway 2004; Eriksson 2005). However, recent molecular data show "… the Micareaceae in its current circumscription belongs in the Lecanorales, but that it is not monophyletic. Psilolechia, Micarea with a 'non-micareoid' photobiont, Micarea sensu stricto and Byssoloma form a paraphyletic grade in this study. Micarea sensu stricto and Byssoloma (Pilocarpaceae) form a strongly supported monophyletic group, which constitutes the sister group to the Bacidiaceae. Scoliciosporum A.Massal., has sometimes been considered close to Micarea, but no support was found for that hypothesis" (Andersen & Ekman 2004: 27). A further study, based on mitochondrial rDNA sequences shows that the family Micareaceae in its current sense is "…highly heterogeneous, and Helocarpon, Psilolechia, and Scutula, all thought to be close relatives of Micarea, are shown to be only distantly related. The genus Micarea is paraphyletic unless the entire Pilocarpaceae and Ectolechiaceae are included… It is suggested that the Micareaceae is reduced to synonymy with the Pilocarpaceae which also includes the Ectolechiaceae, and that Micarea may have to be divided into a series of smaller genera in the future" (Andersen & Ekman 2005).

Species of Micarea have a diverse chemistry, several having gyrophoric acid (C+ red) in apothecia and pycnidia and/or thallus. Alectorialic acid, a xanthone and several unidentified compounds are also found in the genus. Many species have no acetone-soluble compounds. Taxa are found colonising stones, soil, wood or detritus in damp, shaded habitats. Although well-documented from temperate areas of the Northern Hemisphere (Coppins 1983, 1992h; Tønsberg 1992b; Nimis 1993; Santesson 1993), the genus is still poorly known from the Southern Hemisphere (Coppins 1985; Rambold 1989; Coppins & Kantvilas 1990; Filson 1996; Galloway & Quilhot 1999; Fryday 2004), although Coppins & Kantvilas (1990: 277) note "...The numerous collections of microlichens from the Southern Hemisphere, especially from Australasia, indicate that the genus is more or less equally represented in both hemispheres."Micarea is still very poorly collected and studied in New Zealand, where many more additional species may be expected from grassland, scrub and forest biomes. Indeed, work in progress on new species from Tasmania (Kantvilas 2004i), indicates that a number of these newly described species are known also from New Zealand and Chile. The present account records eight species.