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 Edit this classification
Domain: Eukaryota
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 edit

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, it had not been genetically sequenced, so its relationship to other genera in the family is uncertain.[4]

Description edit

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]

References edit

Citations edit

Sources edit

  • "Amazonotrema". Catalogue of Life. Retrieved 15 October 2022.
  • "Amazonotrema". Index Fungorum. Retrieved 13 October 2022.
  • Brodo, Irwin M.; Sharnoff, Sylvia Duran; Sharnoff, Stephen (2001). Lichens of North America. New Haven, CT: Yale University Press. ISBN 0-300-08249-5.
  • Kalb, Klaus (2009). "New taxa and new records of thelotremoid Graphidaceae" (PDF). Herzogia. 22: 17–24.
  • Miranda-González, Ricardo; Lücking, Robert; Barcenas-Peña, Alejandrina & de los Ángeles Herrera-Campos, María (April 2020). "The new genus Jocatoa (Lecanoromycetes: Graphidaceae) and new insights into subfamily Redonographoideae". The Bryologist. 123 (2): 127–143. doi:10.1639/0007-2745-123.2.127. S2CID 215812045.

External links edit