Английская Википедия:Hypogymnia congesta

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Hypogymnia congesta is a rare species of foliose lichen in the family Parmeliaceae. Found in China, it was formally described as a new species in 2003. The lichen grows on the bark and wood of conifers and bamboo. Hypogymnia congesta has a brown to brownish-grey foliose thallus measuring up to Шаблон:Convert long or broad, with a cartilage-like texture. The lichen is chemically distinct, containing physodic acid and virensic acid; the latter substance is otherwise unknown from genus Hypogymnia.

Taxonomy

Hypogymnia congesta was first formally described by lichenologists Bruce McCune and Chicita F. Culberson in 2003. The type specimen was collected near Wei Den village, behind Lou Ma Deng Mountain in Wei Xi County (Yunnan province) at an elevation of Шаблон:Convert.

Description

The thallus of Hypogymnia congest is Шаблон:Lichengloss to somewhat erect and can reach up to Шаблон:Convert in width or length. It has a cartilaginous texture with variable branching patterns, and the Шаблон:Lichengloss are typically 1.7–3.5 mm wide. The upper surface is smooth to weakly Шаблон:Lichengloss and varies in colour from brown to brownish-grey. The lobes often have a pinched and swollen outline, with perforated tips and axils.

This lichen species lacks soredia and isidia, but often has Шаблон:Lichengloss. Apothecia are common, measuring up to 6 mm in diameter. The Шаблон:Lichengloss are 7.0–8.0 by 5.0–5.5 μm in size, and Шаблон:Lichengloss are also common. Шаблон:Lichengloss are rod-shaped to weakly Шаблон:Lichengloss, with dimensions of 5.0–6.0 by 0.8–1.1 μm.

Chemistry

Hypogymnia congesta is unique within its genus for containing virensic acid as a major constituent. Virensic acid produces pale violet-gray spots in thin-layer chromatography, with specific retardation factor (Rf) values that help identify this unique chemical constituent. Other chemical components include atranorin and physodic acid. The Шаблон:Lichengloss and medulla exhibit various colour reactions when tested with different reagents, providing another means to differentiate this species from others. Specifically, in the cortex they are K+ (yellow), C−, KC−, P+ (pale yellow); and in the medulla they are K−, C−, KC−, P+ (slowly yellow orange, often weak).

Habitat and distribution

This lichen species is known to occur only in the type locality.