Frutidella
| Frutidella | |
|---|---|
Scientific classification 
| |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Lecanoromycetes |
| Order: | Lecanorales |
| Family: | Lecanoraceae |
| Genus: | Frutidella Kalb (1994) |
| Type species | |
| Frutidella caesioatra (Schaer.) Kalb (1994)
| |
| Species | |
Frutidella is a genus of lichen-forming fungi in the family Lecanoraceae.[1] It contains three species.[2] The genus was established in 1994 by Klaus Kalb to accommodate a species previously classified in the genus Lecidea. These lichens form thin crusts that often develop distinctive wart-like swellings packed with tiny granules, and they produce small, dome-shaped fruiting bodies with a characteristic blue-green sheen. Species of Frutidella typically grow on acidic substrates, including nutrient-poor soils in upland areas and the bark of trees.
Taxonomy
[edit]The genus was circumscribed in 1994 by Klaus Kalb to contain the species formerly known as Lecidea caesioatra.[3]
Description
[edit]Frutidella grows as a thin crust (crustose thallus) that breaks into discrete, tile-like patches (areoles) or develops conspicuous wart-like swellings. These swellings are packed with tiny, grain-like outgrowths that resemble miniature isidia; as they age the grains can crumble into a powder of soredia, providing a way for the lichen to spread vegetatively. Thallus colour ranges from greenish and grey to bluish or even nearly black, and a narrow white border (prothallus) may or may not be present. The photosynthetic partner is a single-celled green alga of the chlorococcoid type.[4]
The fruiting bodies of Frutidella are small, dome-shaped discs (biatorine apothecia). They sit directly on the thallus, sometimes half-hidden among the surface granules, and appear bluish black or dusted with a blue-grey frost (pruina) when damp. Unlike lichens that recycle thallus tissue to form a rim, these apothecia lack a thalline margin. Instead they are encircled by a true exciple—tightly packed hyphae that radiate like spokes and stay pale or yellowish, never becoming blackened. A crystalline pigment in the surface layer (epithecium) lends a bright blue-green sheen that does not react with potassium hydroxide solution. Beneath, the spore-bearing tissue (hymenium) contains slender, sparsely branched threads (paraphyses) and asci of the Lecanora type, each holding eight smooth, colourless, single-celled ascospores.[4]
Asexual reproduction takes place in minute, flask-shaped structures (pycnidia) that have a darkened tip and release very slender, thread-like conidia. Chemical studies using thin-layer chromatography have detected the secondary metabolite compounds sphaerophorin and thiophanic acid in most specimens, with isoarthothelin or asemone present occasionally.[4]
Ecology
[edit]Species of Frutidella favour acidic substrates. In upland and montane habitats they typically form crusts on nutrient-poor, low-pH soils, where they spread across cushions of mosses. Elsewhere they are mainly corticolous, colonising the acidic bark of trees.[4]
Species
[edit]As of July 2025[update], Species Fungorum (in the Catalogue of Life) accepts three species of Frutidella:[1]
- Frutidella caesioatra (Schaer.) Kalb (1994)
- Frutidella furfuracea (Anzi) M.Westb. & M.Svenss. (2017)
- Frutidella pullata (Norman) Schmull (2011)
References
[edit]- ^ a b "Frutidella". Catalogue of Life. Species 2000: Leiden, the Netherlands. Retrieved 16 July 2025.
- ^ Wijayawardene, N.N.; Hyde, K.D.; Dai, D.Q.; Sánchez-García, M.; Goto, B.T.; Saxena, R.K.; et al. (2022). "Outline of Fungi and fungus-like taxa – 2021". Mycosphere. 13 (1): 53–453 [149]. doi:10.5943/mycosphere/13/1/2. hdl:10481/76378.
- ^ Kalb, K. (1994). "Frutidella, eine neue Flechtengattung für Lecidea caesioatra Schaerer" [Frutidella, a new lichen genus for Lecidea caesioatra Schaerer]. Hoppea Denkschrift der Regensburgischen Naturforschenden Gesellschaft (in German). 55: 581–586.
- ^ a b c d Cannon, P.; Coppins, B.; Aptroot, A.; Fryday, A.; Sanderson, N.; Simkin, J.; Yahr, R. (2024). Miscellaneous Lecanorales including Biatorella (Biatorellaceae), Carbonicola (Carbonicolaceae), Haematomma (Haematommataceae), Psilolechia (Psilolechiaceae), Ramboldia (Ramboldiaceae), Scoliciosporum (Scoliciosporaceae), and Adelolecia, Catinaria, Frutidella, Herteliana, Lithocalla, Myochroidea, Puttea and Schadonia (of uncertain position) (PDF). Revisions of British and Irish Lichens. Vol. 42. p. 14.
