Micarea Explained
Micarea is a genus of lichenized fungi in the family Pilocarpaceae. The widely distributed genus contains 126 species and new species are described actively. Species in the genus are crustose lichens and their photobiont (the non-fungal organism) is a single-celled green alga.
Taxonomy
Micarea was circumscribed by Elias Magnus Fries in his 1825 work Systema Orbis Vegetabilis. There have been some taxonomic disputes about the genus. Nowadays, the genus is accepted, although it is paraphyletic and in need of further research. Micarea prasina is the type species of the genus.
Reproduction
Lichenized fungi have developed diverse reproduction strategies. The microlichen genus Micarea is an excellent model for studying the effects of reproductive traits and environmental factors on speciation because it shows intricate variation in substrate requirements and reproduction modes. Certain Micarea species are generalists and able to grow on various substrata, while some are specialized and live in strict microhabitats. Some of the Micarea species are predominately sexual, while some frequently lack sexual structures but bear numerous pycnidia where asexual conidia are produced. The actual roles of the three types of conidia present are not thoroughly understood, but mesoconidia are likely asexual propagules based on, for example, the observation that many of the species are frequently found with only mesopycnidia and no apothecia. Recent phylogenetic analyses together with ancestral state reconstruction among Micarea species showed that the shift in reproduction mode has evolved independently several times within the group and that facultative and obligate lignicoles are sister species. This supports the assumption that the ancestor of these species was a facultative lignicole. It is presumed that a shift in substrate requirement from bark to wood leads to differentiation in reproduction mode and becomes a driver of speciation in Micarea microlichens. The case of Micarea is the first observation that among lichenized fungi reproduction mode is connected to substrate requirement. It is also the first example where such an association is demonstrated to lead to lichen speciation. The main hypothesis behind this phenomenon is that obligate species on dead wood need to colonize new suitable substrata relatively fast and asexual reproduction is a more effective strategy for successful colonisation.
Species
, Species Fungorum accepts 126 species of Micarea, although this tally does not yet include some recently described taxa, such as four species from montane cloud forests of Kenya.
- Micarea adnata
- Micarea aeruginoprasina
- Micarea alabastrites
- Micarea alectorialica
- Micarea amplissima
- Micarea argopsinosa
- Micarea assimilata
- Micarea austroternaria – Australia
- Micarea azorica
- Micarea bacidiella
- Micarea bebourensis
- Micarea borbonica
- Micarea boryana
- Micarea botryoides
- Micarea byssacea
- Micarea canariensis
- Micarea capitata
- Micarea ceracea – Australasia
- Micarea ceylanica
- Micarea cilaosensis
- Micarea cinerea
- Micarea cinereopallida – Australasia; South America
- Micarea contexta
- Micarea coppinsii
- Micarea corallothallina
- Micarea coreana
- Micarea crassa
- Micarea curvata
- Micarea czarnotae
- Micarea deminuta
- Micarea denigrata
- Micarea doliiformis
- Micarea elachista
- Micarea epiphylla
- Micarea eucalypti
- Micarea eximia
- Micarea fallax
- Micarea farinosa
- Micarea fennica
- Micarea flagellispora – Australasia
- Micarea flavoleprosa
- Micarea globulosella
- Micarea granuloblastidiata – Panama
- Micarea hedlundii
- Micarea herbarum – Europe
- Micarea humilis – Australia
- Micarea hyalinoxanthonica
- Micarea hylocomii
- Micarea hypoviolascens
- Micarea incrassata
- Micarea inquinans
- Micarea intersociella
- Micarea isabellina – Australia
- Micarea isidioprasina
- Micarea isidiosa
- Micarea kartana – Australia
- Micarea kemmleri
- Micarea laeta
- Micarea lapillicola
- Micarea leprosula
- Micarea levicula
- Micarea lignaria
- Micarea lithinella
- Micarea longispora
- Micarea magellanica
- Micarea marginata
- Micarea melaena
- Micarea melaenida
- Micarea melanobola
- Micarea melanoprasina
- Micarea meridionalis – Europe
- Micarea microareolata
- Micarea micrococca
- Micarea micromelaena – Australasia
- Micarea microsorediata
- Micarea minuta – western Europe
- Micarea misella
- Micarea mutabilis – Australia
- Micarea myriocarpa
- Micarea neostipitata – eastern North America
- Micarea nigella
- Micarea nigra
- Micarea nigrata
- Micarea nitschkeana
- Micarea nowakii
- Micarea olivacea
- Micarea oreina – Australasia
- Micarea pallida – Australasia
- Micarea pannarica
- Micarea parasitica
- Micarea paratropa
- Micarea parva
- Micarea pauli
- Micarea peliocarpa
- Micarea poliocheila
- Micarea polycarpella
- Micarea prasina
- Micarea prasinastra – Australasia
- Micarea prasinella
- Micarea pseudocoppinsii
- Micarea pseudolignaria
- Micarea pseudomarginata
- Micarea pseudomicrococca
- Micarea pseudotsugae – western Europe
- Micarea pumila – Kenya
- Micarea pusilla
- Micarea pycnidiophora
- Micarea queenslandica
- Micarea rubiformis
- Micarea rubiginosa – Australasia; South America
- Micarea rubioides
- Micarea sambuci
- Micarea sandyana – Australasia
- Micarea saxicola – Australasia
- Micarea senecionis
- Micarea sipmanii
- Micarea soralifera
- Micarea squamulosa
- Micarea stellaris – Kenya
- Micarea stereocaulorum
- Micarea stipitata
- Micarea subalpina
- Micarea subcinerea
- Micarea subconfusa
- Micarea subgranulans
- Micarea sublithinella
- Micarea submilliaria
- Micarea subnigrata
- Micarea subternaria
- Micarea subviridescens
- Micarea synotheoides
- Micarea taitensis – Kenya
- Micarea takamakae
- Micarea tenuispora
- Micarea termitophila
- Micarea ternaria
- Micarea tomentosa
- Micarea tubaeformis – Australasia
- Micarea turfosa
- Micarea usneae – Madeira
- Micarea versicolor – Kenya
- Micarea viridiatra – Europe
- Micarea viridicapitata – Mexico
- Micarea viridileprosa – western Europe
- Micarea vulpinaris
- Micarea xanthonica – Europe; North America