Gonotichia

Gonotichia
Scientific classification
Kingdom: Fungi
Division: Ascomycota
Class: Lichinomycetes
Order: Lichinales
Family: Lichinellaceae
Genus: Gonotichia
M.Schultz & M.Prieto (2024)
Type species
Gonotichia octosporella
(Lettau) M.Schultz & M.Prieto (2024)
Species

G. depauperata
G. octosporella

Gonotichia is a small genus of cyanolichens (lichens that partner with cyanobacteria) in the family Lichinellaceae. The genus was established in 2024 as part of a major reorganisation of cyanolichen classification based on DNA studies, and contains just two species that form tiny, dark crusts on sun-exposed rocks. These lichens are characterised by their distinctive reproductive structures that develop as swellings within the lichen body rather than as separate disc-like structures on the surface.

Taxonomy

The genus was circumscribed by Matthias Schultz and María Prieto as part of a class-wide phylogenetic revision that reorganised Lichinomycetes into four families (three emended and one new). Within this scheme, Gonotichia forms a distinct clade in Lichinellaceae, which the authors diagnose chiefly by thallinocarpous ascomata and a Lichinella-type ascus. The type species is Gonotichia octosporella, a taxon that was originally described as Gonohymenia octosporella by Georg Lettau in 1942.[1] A second species, G. depauperata (originally described as Gonohymenia myriospora var. depauperata by Miroslav Servít in 1937[2]), was also included in the original treatment.[3]

Description

Species of Gonotichia are minute, rock-dwelling cyanolichens. The thallus (lichen body) is crustose, forming thin, dark, irregular patches (areoles) on the substrate rather than a leafy or shrubby form. The sexual reproductive structures are thallinocarpous, i.e. the ascomata develop within swellings of the thallus instead of as open, disc-like apothecia on the surface. Asci conform to the Lichinella-type used to characterise Lichinellaceae; in the type species they bear eight ascospores.[3]

Habitat and distribution

Gonotichia species occur on sun-exposed mineral substrates, especially siliceous rock, in open sites. Their very small, dark crusts are typical of many Lichinellaceae, which are scattered but widespread in suitable dry, well-lit habitats.[3]

Species

The following species are accepted in the 2024 treatment:[3]

  • Gonotichia depauperata (Servít) M.Schultz & M.Prieto (2024)
  • Gonotichia octosporella (Lettau) M.Schultz & M.Prieto (2024)

References

  1. ^ Lettau, G. (1942). "Flechten aus Mitteleuropa. VII". Feddes Repertorium Specierum Novarum Regni Vegetabilis Beiheft (in German). 119 (5): 265–348 [269].
  2. ^ Servít, M. (1937). "Seltenere und neue Flechten". Vestnik Královske Ceské Spolecnosti Nauk (in German). 1936: 1–16 [7].
  3. ^ a b c d Prieto, M.; Wedin, M.; Schultz, M. (2024). "Phylogeny, evolution and a re-classification of the Lichinomycetes". Studies in Mycology. 109: 595–655. doi:10.3114/sim.2024.109.09. PMC 11663425. PMID 39717657.