Amazonotrema
Genus of lichen
From Wikipedia, the free encyclopedia
Amazonotrema is a monotypic genus of lichenised fungi in the family Graphidaceae.[1] It was circumscribed in 2009 by Klaus Kalb and Robert Lücking for the species Amazonotrema nigrum.[2][3] The type specimen of A. nigrum was collected from virgin rainforest along the Rio Negro in the Brazilian state of Amazonas.
| Amazonotrema | |
|---|---|
Scientific classification  | |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Graphidales |
| Family: | Graphidaceae |
| Genus: | Amazonotrema Kalb & Lücking (2009) |
| Species: | A. nigrum |
| Binomial name | |
| Amazonotrema nigrum Kalb & Lücking (2009) | |
Taxonomy
The genus name is a combination of Amazon, for the Amazon basin region from which the type specimen was collected, and trema, for the systematic position of the genus within the family Graphidaceae; it falls into the "thelotremoid" group because of the structure of its fruiting bodies (apothecia).[3] As of 2020[update], it had not been genetically sequenced, so its relationship to other genera in the family is uncertain.[4]
Description
Amazonotrema nigrum is a crustose lichen with a smooth, grey, and somewhat glossy surface, and it grows on tree bark, stripped wood and tree fern stems.[3] Unlike most plant-dwelling lichens (but like many other tropical, crustose lichens),[5] it lives partially immersed in the bark or stems on which it grows – a strategy known as endophloeodal.[3] Its apothecia, which tend to be dispersed across the lichen's surface, are steep-sided, broadly rounded at the apex, and the same colour as the thallus.[6] The apothecia's central disc is typically black, which is what led to the scientific name nigrum. [3] It is not known to have either isidia or soralia (two lichen structures which allow vegetative reproduction).[7]
Each ascus within the apothecia contains 5–8 ascospores, which are chestnut-brown in colour and arranged in rows. The spores themselves are muriform – divided into smaller compartments by intersecting partitions known as septa.[7]
The lichen produces several secondary metabolites, including stictic acid and constictic acid.[7]