Xanthomendoza fallax (Hepp) Sochting, Körnefelt & S. Y. Kondr.

   Thallus foliose, in rosettes of 2-3 cm in their greatest length but which can combine to cover a larger area, formed of narrow lobes 2-3 mm in width, flat towards the margin, indented and a little webbed, upper surface smooth, orange, golden yellow, orange yellow, presence of powdery yellow soralia, marginal and labriform, white underside with few rhizines. Apothecia rare, sessile, 0.5-2.5 mm in diameter, flat orange disc, paler margin sometimes soredate. Asci with 4-6- (8) spores, 50-60 x 17-21 µm according to our measurements. Polarilocular spores, hyaline, elliptical, 12-17 x 6-9 µm with an equatorial thickening of 4-5 mm according to the literature; 13-17 x 5-8 µm according to our measurements. Photobiont: Trebouxia. K +: purple. Species with thermophilic trends, saxicolous and occurng on siliceous rocks, rarely corticole. Cf. Xanthomendoza huculica formerly confused, corticole with wider lobes, soralia arranged in hoods and narrower spores arranged at 8 per ascus.