Английская Википедия:Astrothelium graphicum
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Astrothelium graphicum is a species of lichen in the family Trypetheliaceae.[1] This lichen features an extended, reticulate Шаблон:Lichengloss that is lower than its slightly Шаблон:Lichengloss thallus.
Taxonomy
The species was formally described as new to science in 2016 by the lichenologists André Aptroot and Suzana Maria de Azevedo Martins. The type collection was made in Santarém, Pará, Brazil, in September 2013.[2]
Description
The thallus of Astrothelium graphicum is Шаблон:Lichengloss, smooth to somewhat Шаблон:Lichengloss, and somewhat shiny. It is continuous, covering areas up to Шаблон:Convert in diameter and approximately 0.3 mm thick. The thallus is green with a thin orange Шаблон:Lichengloss and is not surrounded by a Шаблон:Lichengloss. It does not induce gall formation on the host bark.[2]
Шаблон:Lichengloss are spherical, measuring 0.3–0.4 mm in diameter, and are mostly aggregated in groups of 10–40. They are immersed in or even below the Шаблон:Lichengloss, which have a surface distinct from the thallus. The pseudostromata are not distinctly lower than the thallus, irregular in outline, anastomosing to meandering in a reticulate pattern, and can reach up to about 5 mm in diameter. They are ochraceous with a thin orange pruina, and the inside is also ochraceous without containing bark tissue. The wall is Шаблон:Lichengloss and up to about 80 μm thick. Ostioles are apical, not fused, flat, ochraceous to brown, and surrounded by a whitish to ochraceous, often clearly exserted ring of about 0.1 mm. The Шаблон:Lichengloss does not have oil globules interspersed. Asci contain 8 Шаблон:Lichengloss each. Ascospores are hyaline, Шаблон:Lichengloss, ellipsoid, measuring 60–66 by 12–16 μm, without a distinctly thickened median septum, with rounded ends, and not surrounded by a gelatinous layer. Шаблон:Lichengloss have not been observed in this species.[2]
Similar species
Astrothelium graphicum is characterised by its extended, reticulate pseudostroma, lower than the slightly bullate thallus, and the orange pruina on both the thallus and pseudostroma, which gives it a resemblance to a giraffe's pattern. It is similar in aspect to A. flavomaculatum, which mainly differs by its much larger ascospores, measuring 140–200 by 25–30 μm.[2]
Chemistry
The thallus surface of Astrothelium graphicum reacts to UV light with a pink colour, and its medulla is K−. The pseudostroma surface also reacts to UV light with a pink colour, and the pigmented parts of the pseudostroma turn K+ (purple). Thin-layer chromatography, a technique used to identify chemical substances, reveals the presence of an anthraquinone, likely parietin.[2]
Habitat and distribution
This lichen grows on smooth bark of trees in rainforests. At the time of its original publication, it was known only from Brazil.[2]
References
