Biology:Astrothelium lineatum
| Astrothelium lineatum | |
|---|---|
Scientific classification 
| |
| Kingdom: | Fungi |
| Division: | Ascomycota |
| Class: | Dothideomycetes |
| Order: | Trypetheliales |
| Family: | Trypetheliaceae |
| Genus: | Astrothelium |
| Species: | A. lineatum
|
| Binomial name | |
| Astrothelium lineatum Aptroot & M.Cáceres (2016)
| |
Astrothelium lineatum is a species of corticolous (bark-dwelling) crustose lichen in the family Trypetheliaceae.[1] This lichen was discovered in the Brazilian Amazon, where it grows on tree bark in savanna areas. It is distinguished by its bright orange coloring and the linear patterns formed by its ascospore-producing structures.
Taxonomy
Astrothelium lineatum was described as new to science in 2016 by André Aptroot and Marcela da Silva Cáceres from material collected in Amapá, northern Brazil. The holotype was gathered on tree bark in savanna vegetation near the Maracá Extractive Reserve (municipality of Mazagão, Amapá). The specific epithet refers to the species' often linear [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]].[2]
In their notes, the authors indicated that it keys near Astrothelium condoricum, but that species lacks the red pigmentation in the [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]] and has shorter, wider spores without a gelatinous sheath.[2]
Description
The thallus of A. lineatum is dull ochraceous and entirely suffused with bright orange pigment. It lacks a distinct [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]] and appears to induce gall-like swelling of the host bark. Ascomata (fruiting structures) are roughly spherical ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]) to pear-shaped ([[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]), 0.5–0.8 mm in diameter, and occur deeply [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]] in and beneath the pseudostromata in groups of 3–15. Pseudostromata are only weakly differentiated from the thallus, ellipsoid to elongated or branched (sometimes forming a [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]), and orange on the surface but unpigmented internally. The ostioles are apical, pale brown, and encircled by a roughly 0.1 mm whitish ring. The [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]] is not [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]]. Asci contain eight ascospores; the spores are hyaline, regularly [[Glossary of lichen terms#{{biology:{1}}}|{{Biology:{1}}}]], long-ellipsoid, 45–55 × 11–13 μm, without a distinctly thickened median septum, and are surrounded by a 10–13 μm-wide gelatinous sheath. Pycnidia were not observed to occur in this species.[2]
In terms of spot test reactions, the thallus and pseudostroma are UV+ (pink) and K+ (blood red); thin-layer chromatography detected an anthraquinone, probably parietin.[2]
Habitat and distribution
The species grows on tree bark in savanna vegetation and is known to occur only in Amapá, Brazil.[2][3]
See also
- List of lichens of Brazil
References
- ↑ "Astrothelium lineatum Aptroot & M. Cáceres". Species 2000: Leiden, the Netherlands. https://www.catalogueoflife.org/data/taxon/J5FL.
- ↑ 2.0 2.1 2.2 2.3 2.4 Cáceres, Marcela Eugenia da Silva; Aptroot, André (2016). "First inventory of lichens from the Brazilian Amazon in Amapá State". The Bryologist 119 (3): 250–265. doi:10.1639/0007-2745-119.3.250. https://www.researchgate.net/publication/307904602.
- ↑ Aptroot, André; da Silva Cáceres, Marcela Eugenia; dos Santos, Lidiane Alves; Benatti, Michel N.; Canêz, Luciana; Forno, Manuela Dal et al. (2025). "The Brazilian lichen checklist: 4,828 accepted taxa constitute a country-level world record". The Bryologist 128 (2): 96–423 [131]. doi:10.1639/0007-2745-128.2.96.
Wikidata ☰ Q27890484 entry
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