Phaeophyscia endophoenicea
Phaeophyscia endophoenicea is a species of corticolous foliose lichen in the family Physciaceae. It is characterized by a grey to pale brown rosette-forming thallus that grows 1–3 cm wide. It features narrow with yellowish to reddish powdery reproductive structures called soredia, and a distinctive black lower surface with abundant root-like rhizines that anchor it to its substrate. The lichen's inner tissue is typically yellow to orange-red in its lower part. Though rare and possibly underreported, P. endophoenicea primarily grows on the bark of slanting trees across various European regions, extending from southern areas into Scandinavia, with presence in relatively undisturbed forests of European Russia, Ukraine, and the Netherlands.
Taxonomy
The species was first described in 1910 by the French lichenologist Julien Herbert Auguste Jules Harmand, who classified it as a variety of Physcia obscura. Roland Moberg elevated it to distinct species status in his 1977 monograph on the genus Physcia.Description
Phaeophyscia endophoenicea is a foliose lichen characterised by a, thallus that forms orbicular to more commonly irregular rosettes measuring 1–3 cm in width. The thallus is narrow-lobed and closely to the substrate in the central portion.The are grey to pale brown in specimens exposed to sunlight, typically measuring 1–1.5 mm in width. They appear dull to weakly shiny, lack, and feature ascending tips. The lobes develop terminal, soralia, with soralia often present as well. The soredia are frequently yellowish to reddish due to the exposed medulla, appearing in texture, with individual soredia typically less than 40 μm in diameter.
The lower surface of the thallus is black and has abundant, black, simple rhizines. The upper is and exceeds 22 μm in thickness. The medulla is characteristically yellow to orange-red in its lower part, though rarely white throughout. The lower cortex is also paraplectenchymatous in structure.
Apothecia are rare and in form. The is brown, while both the hymenium and are colourless. The paraphyses are slender and often forked in their upper portions, with apical cells featuring a thin dark cap.
The asci are clavate and contain eight spores each. They have a K/I+ blue penetrated by a faintly amyloid apical cushion with parallel or diverging flanks. The wall is K/I−, but is surrounded by a K/I+ blue outer layer, conforming to the Lecanora-type. The ascospores are 1-septate, brown, ellipsoid, measuring 23–28 by 9–11 μm, and are of the Physcia-type. Pycnidia are rare.
The is . The medulla typically contains the pigment skyrin and lacks fatty acids.