Huriopsis


Huriopsis is a genus of lichen-forming fungi in the family Physciaceae. The genus was established in 2021 through molecular phylogenetics analysis that revealed the polyphyletic nature of the traditional genus Rinodina. Species of Huriopsis are characterised by their distinctive golden-yellow thalli and the presence of xanthone pigments, particularly thiomelin.

Taxonomy

Huriopsis was introduced in 2021 by Sergey Kondratyuk and László Lőkös as part of a broad molecular re-evaluation of the Physciaceae. It was carved out of the polyphyletic catch-all Rinodina to accommodate the "Rinodina xanthophaea" group, with Huriopsis xanthophaea designated as the type species and the genus name honouring Jae-Seoun Hur. The authors justified the segregation on a mix of molecular and diagnostic characters: species of Huriopsis typically have a citrine thallus or yellow-green soralia, thick-walled ascospores, and xanthone pigments such as thiomelin in the or medulla. These features set them apart from superficially similar Rinodina taxa.

Description

Species of Huriopsis are crustose lichens with a thin to moderately thick thallus that is golden yellow to grey, either continuous or broken into small, with a, even surface. Asexual propagules may be present or absent; when present they are typically yellow-green. Powdery reproductive patches commonly begin as narrow, lip-like breaks along the margin and round off into small circular spots, sometimes becoming. The powder can clump into larger that may form tiny bud-like fragments; true isidia also occur in some species. A black is usual, forming a neat border that can become thick and ragged where the lichen spreads over other crusts or foliose lichens.
Sexual structures, when produced, are small apothecia attached by a narrow base; the is plane and dark reddish-brown, with a rim of thallus tissue matching the thallus colour that remains flexuous and persistent. Orange-red crystals occur in the cortex of the apothecial rim and in the medulla and can obscure tissue detail. Ascospores show "type A" development and are of the Physcia- or Pachysporaria-type, with smooth walls. Chemically, the genus contains xanthone pigments and usually secalonic acid A or W, sometimes with traces of atranorin; routine spot tests are typically K−, C+, KC+, P−, and UV+. In combination with the yellow thallus or yellow-green soralia, these distinguish Huriopsis from superficially similar Rinodina.

Species

Huriopsis chrysidiata Huriopsis lepida Huriopsis luteonigra Huriopsis plana Huriopsis thiomela Huriopsis xanthomelana Huriopsis xanthophaea
One of the proposed recombinations, Huriopsis chrysomelaena, based on Erik Acharius's 1814 Lecanora chrysomelaena, was invalidly published. In the protologue the basionym was cited as "Rinodina chrysomelaena Tuck., Genera Lichenum : 123 ", rather than giving a full and direct reference to the place of publication of the true basionym as required by Article 41.5 of the Shenzhen Code; accordingly Index Fungorum lists the name as nomen invalidum.