Oxneria ussuriensis
Oxneria ussuriensis is a species of corticolous, crustose lichen in the family Teloschistaceae. It is found in a single location in the Russian Far East.
Taxonomy
The lichen was formally described as a new species in 2014 by lichenologists Sergey Kondratyuk, Soon-Ok Oh, and Jae-Seoun Hur. The type specimen was collected by the first author from a park in Kraskino, where he found it growing on a Populus tree. The species epithet refers to the type locality.Description
Oxneria ussuriensis has a deep orange to orange-yellow rosette-like thallus that has a diameter of. The individual lobes comprising the thallus are 1.5–2 mm long, and have a width that ranges from 0.3 to 0.7 mm in the narrowest parts to 1 mm in the widest parts. The terminal parts of the lobes sometimes branch out to form secondary lobes or lobules. The underside of the lobes are covered with bluish-greyish soredia. Individual soredia are irregularly elongated and have a diameter from 20 to 50 μm; sometimes soredia aggregate into larger structures that are irregularly rounded with a diameter of 60–70 μm.The apothecia made by Oxneria ussuriensis are lecanorine in form with a diameter of 0.6–1.7 mm and a bright orange disc that is either flat or somewhat concave. Ascospores have a narrow ellipsoidal shape and dimensions of 9–23 by 5.5–10 μm.
Xanthomendoza huculica, found in Ukraine, is somewhat similar in appearance and morphology to Oxneria ussuriensis, but X. huculica has a larger thallus made of larger lobes, and its spores have a smaller length range and are thinner.