{{Short description|Genus of lichen-forming fungi}} {{Use dmy dates|date=January 2024}} {{Use Oxford spelling|date=January 2025}} {{Automatic taxobox | image = Lecanora carpinea 61571238.jpg | image_caption = ''Glaucomaria carpinea'' | taxon = Glaucomaria | authority = M.Choisy (1929) | type_species = Glaucomaria rupicola | type_species_authority = (L.) P.F.Cannon (2022) | subdivision_ranks = Species | subdivision = ''G. bicincta''<br /> ''G. bicinctoidea''<br /> ''G. carpinea''<br /> ''G. flavescens''<br /> ''G. leptyrodes''<br /> ''G. lojkaeana''<br /> ''G. rupicola''<br /> ''G. subcarpinea''<br /> ''G. swartzii'' }}
'''''Glaucomaria''''' is a genus of lichen-forming fungi in the family Lecanoraceae.<ref name="CoL"/> Species in this genus have a crust-like growth form and are distinguished by their heavily powdery fruiting bodies, which produce a bright lemon-yellow colour when treated with bleach. The genus occurs on both tree bark and siliceous rock across most continents, though it is absent from Antarctica. All species produce the compounds sordidone and atranorin as their main secondary metabolites.
==Taxonomy== In 2025, a multi-locus phylogenetic study of ''Lecanora'' sensu lato (based on seven DNA loci, including mitochondrial markers) recovered several well-supported clades and supported the resurrection of ''Glaucomaria'' for the former ''Lecanora carpinea''/''L. rupicola'' group. Before its resurrection as ''Glaucomaria'', these species were usually discussed within ''Lecanora'' as part of the "''Lecanora rupicola'' group" (or a rupicola species complex) in earlier phylogenetic and phenotypic work.<ref name="Grube et al. 2004"/><ref name="Blaha & Grube 2007"/><ref name="Zhao et al. 2015"/>
The name ''Glaucomaria'' was introduced by Maurice Choisy in 1929 for a set of lecanoroid lichens with heavily pruinose apothecia and a typically pale epithecium; the type species is ''Glaucomaria rupicola''.<ref name="Choisy 1929"/><ref name="Ivanovich-Hichins et al. 2025"/>
==Description== ''Glaucomaria'' is characterized by a crust-like (crustose) thallus, which is sometimes spread out with a radiating pattern ({{lichengloss|placodioid}}). The colour of the thallus ranges from white-yellowish green to pale grey. The apothecia (fruiting bodies) initially grow attached ({{lichengloss|adnate}}) and can become slightly raised ({{lichengloss|sessile}}) or nearly stalked (substipitate). These apothecia feature a heavily powdery ({{lichengloss|pruinose}}) {{lichengloss|disc}} that reacts to the C spot test to produce an intense lemon-yellow colour. The margin of the apothecia is persistent, sometimes being pushed aside (finally excluded), and occasionally surrounded by a black, wavy ({{lichengloss|flexuose}}) ring.<ref name="ITALIC"/>
The outer layer of the apothecia ({{lichengloss|thalline exciple}}) typically has a {{lichengloss|phenocortex|phenocorticate}} cortex (containing hyphal fragments and dead, collapsed algal cells), numerous algal cells, and both large and small crystals, with the latter dissolving in a solution of potassium hydroxide (K). The inner layer ({{lichengloss|proper exciple}}) ranges from thin to thick, dark on the outside and upper part but colourless inside. The {{lichengloss|epithecium}} (topmost layer of the apothecia) is brown to dark brown with crystals, both the pigment and crystals dissolving in K. The hymenium, the spore-producing layer, is colourless and does not contain oil droplets. The paraphyses (sterile filaments in the hymenium) are slightly thickened at the top. The layer below the hymenium ({{lichengloss|hypothecium}}) is colourless and not interspersed with droplets.<ref name="ITALIC"/>
The asci (spore-bearing cells) of ''Glaucomaria'' are club-shaped ({{lichengloss|clavate}}) and very thin-walled. They contain a tall structure in the middle ({{lichengloss|tholus}}) that reacts to iodine and potassium hydroxide by turning blue (K/I+ blue), surrounded by a blue outer layer (''Lecanora''-type). The {{lichengloss|ascospores}} are single-celled, hyaline (translucent), ellipsoid, and have a wall less than 1 μm thick. The {{lichengloss|photobiont}}, the photosynthetic partner of the lichen, is {{lichengloss|chlorococcoid}} a type of green algae (chlorococcoid).<ref name="ITALIC"/>
Most species have an episubstratal, whitish to grey thallus that is usually esorediate, although some taxa are sorediate; isidia are absent. Species occur both on bark and on siliceous rock, and the genus is subcosmopolitan, being recorded from most continents but absent from Antarctica.<ref name="Ivanovich-Hichins et al. 2025"/>
==Chemistry==
All ''Glaucomaria'' species produce the chromone compound sordidone and atranorin as major secondary metabolites, with chloroatranorin and/or eugenitol as frequent minor substances. Many saxicolous species also contain roccellic acid, and some taxa produce psoromic acid and xanthones such as arthothelin and thiophanic acid (and related compounds).<ref name="Ivanovich-Hichins et al. 2025"/>
==Species==
*''Glaucomaria bicincta'' {{au|(Ramond) S.Y.Kondr., Lőkös & Farkas (2019)}} * ''Glaucomaria bicinctoidea'' {{au|(Blaha & Grube) Ivanovich-Hichins (2025)}} * ''Glaucomaria carpinea'' {{au|(L.) S.Y.Kondr., Lőkös & Farkas (2019)}} * ''Glaucomaria flavescens'' {{au|(Cl.Roux & Tønsberg) Ivanovich-Hichins (2025)}} * ''Glaucomaria leptyrodes'' {{au|(Nyl.) Ivanovich-Hichins & Printzen (2025)}} * ''Glaucomaria lojkaeana'' {{au|(Szatala) S.Y.Kondr., Lőkös & Farkas (2019)}} * ''Glaucomaria rupicola'' {{au|(L.) P.F.Cannon (2022)}} * ''Glaucomaria subcarpinea'' {{au|(Szatala) S.Y.Kondr., Lőkös & Farkas (2019)}} * ''Glaucomaria swartzii'' {{au|(Ach.) S.Y.Kondr., Lőkös & Farkas (2019)}}
==References== {{Reflist|colwidth=30em|refs=
<ref name="Blaha & Grube 2007">{{cite journal |last1=Blaha |first1=J. |last2=Grube |first2=M. |year=2007 |title=The new species ''Lecanora bicinctoidea'', its position and considerations about phenotypic evolution in the ''Lecanora rupicola'' group |journal=Mycologia |volume=99 |issue=1 |pages=50–58 |jstor=20444806 |doi=10.1080/15572536.2007.11832600 |pmid=17663123}}</ref>
<ref name="Choisy 1929">{{cite journal |last=Choisy |first=M. |year=1929 |title=Genres nouveaux pour la lichénologie dans le groupe des Lecanoracées |journal=Bulletin de la Société Botanique de France |volume=76 |issue=3 |pages=521–527 |doi=10.1080/00378941.1929.10837179 |bibcode=1929BSBF...76..521C |language=fr}}</ref>
<ref name="CoL">{{Catalogue of Life |id=62SG9 |title=''Glaucomaria'' |access-date=18 January 2024}}</ref>
<ref name="Grube et al. 2004">{{cite journal |last1=Grube |first1=Martin |last2=Baloch |first2=Elisabeth |last3=Arup |first3=Ulf |year=2004 |title=A phylogenetic study of the ''Lecanora rupicola'' group (Lecanoraceae, Ascomycota) |journal=Mycological Research |volume=108 |issue=5 |pages=506–514 |doi=10.1017/S0953756204009888|pmid=15230003 |url=https://lup.lub.lu.se/record/137475}}</ref>
<ref name="ITALIC">{{cite web |last1=Nimis |first1=P.L. |last2=Martellos |first2=S. |title=''Glaucomaria'' |website=ITALIC 7.0 |url=https://italic.units.it/index.php?procedure=genuspage&ID_genus=481 |access-date=18 January 2024}}</ref>
<ref name="Ivanovich-Hichins et al. 2025">{{cite journal |last1=Ivanovich-Hichins |first1=Cristóbal |last2=Weber |first2=Lilith |last3=Li |first3=Lijuan |last4=Leavitt |first4=Steven D. |last5=Muggia |first5=Lucia |last6=Palice |first6=Zdenek |last7=Pérez-Ortega |first7=Sergio |last8=Sohrabi |first8=Mohammad |last9=Printzen |first9=Christian |title=New phylogenetic insights into the lichen genus ''Lecanora'' s. lat. (Lecanoraceae, Ascomycota): resurrection of the genera ''Glaucomaria'', ''Straminella'' and ''Zeora'' |journal=The Lichenologist |volume=57 |issue=6 |year=2025 |doi=10.1017/S0024282925101321 |pages=278–303|doi-access=free |hdl=10261/417443 |hdl-access=free }}</ref>
<ref name="Zhao et al. 2015">{{cite journal |last1=Zhao |first1=X. |last2=Leavitt |first2=S.D. |last3=Zhao |first3=Z.T. |last4=Zhang |first4=L.L. |last5=Arup |first5=U. |last6=Grube |first6=M. |last7=Pérez-Ortega |first7=S. |last8=Printzen |first8=C. |last9=Śliwa |first9=L. |last10=Kraichak |first10=E. |last11=Divakar |first11=P.K. |last12=Crespo |first12=A. |last13=Lumbsch |first13=H.T. |year=2015 |title=Towards a revised generic classification of lecanoroid lichens (Lecanoraceae, Ascomycota) based on molecular, morphological and chemical evidence |journal=Fungal Diversity |volume=78 |pages=293–304 |doi=10.1007/s13225-015-0354-5}}</ref>
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Category:Lecanoraceae Category:Lecanorales genera Category:Lichen genera Category:Taxa described in 1929 Category:Taxa named by Maurice Choisy