| Teuvoahtiana | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Teloschistales |
| Family: | Teloschistaceae |
| Genus: | Teuvoahtiana S.Y.Kondr. & Hur (2017) |
| Type species | |
| Teuvoahtiana rugulosa (Nyl.) S.Y.Kondr. & Hur (2017) | |
Teuvoahtiana is a genus of lichen-forming fungi in the family Teloschistaceae. [1] [2] It contains three species of saxicolous (rock-dwelling), crustose lichens, all of which occur in South America.
Teuvoahtiana was circumscribed in 2017 by lichenologists Sergey Kondratyuk and Jae-Seoun Hur, with Teuvoahtiana rugulosa assigned as the type species. [3] This species was first formally described as Placodium rugolosum by William Nylander in 1855. [4] The genus name honours Finnish lichenologist Teuvo Ahti, "in recognition of his contribution to lichenology and especially to development of lichenological investigation in the South American continent". [3]
Teuvoahtiana has members that are crustose, areolate , and squamulose –an unusually diverse range of forms for a single monophyletic branch of the Teloschistaceae. In some cases, the peripheral zone of the thallus has unique areoles that are elongated to form distinct lobes . This genus is noted for the pronounced thickness of the areolae and lobes. Their colour ranges from a luminescent yellow-orange to a more muted yellowish-brown or dull orange-brown. When numerous apothecia are present, the thallus can take on a less common reddish-orange-brown shade. Structurally, the cortical layer transitions between a paraplectenchymatous to a mesodermatous paraplectenchymatous state. [3]
The apothecia of Teuvoahtiana vary from medium to large size, often congregating in dense clusters. They have a lecanorine to zeorine structure, with a flat disc that displays a spectrum of colours from soft yellow to a more vibrant pinkish orange-brown. The true exciple , or outer layer, is characterised by a complex interwoven structure, known as " textura intricata ". The asci, the reproductive sacs in which spores are formed, hold a variable count of one to eight spores. These ascospores are polarilocular (divided into two compartments by a thick septum with a perforation). [3]
Teuvoahtiana is similar to the Australian genus Filsoniana , but unlike that genus, is in the subfamily Xanthorioideae rather than subfamily Teloschistoideae. Close relatives of Teuvoahtiana include the genera Xanthopeltis and Austroplaca . [3]
The new species Teuvoahtiana meridionalis was recently (2023) described from Antarctica and Southern South America. [5]