{{Short description|Species of lichen-forming fungus}} {{Use mdy dates|date=January 2026}} {{Use American English|date=January 2026}} {{Speciesbox | image = | image_caption = | taxon = Pyxine jolyana | authority = Jungbluth, [[Klaus Kalb|Kalb]] & Marcelli (2011) | mapframe = yes | mapframe-zoom = 3 | mapframe-coordinates = {{coord|24|24|58|S|47|02|57|W}} | mapframe-caption = [[type locality (biology)|Type locality]]: [[Jureia-Itatins Ecological Station]], Brazil<ref name="Jungbluth et al. 2011"/> }}

'''''Pyxine jolyana''''' is a species of [[foliose lichen]] in the family [[Caliciaceae]].<ref name="CoL_4QYK3"/> It is known from southeastern Brazil, where it grows on rocks and tree bark in coastal and near-coastal areas from sea level to about {{cvt|915|m|-1}} elevation. The species is distinguished by its brownish-gray [[rosette (botany)|rosettes]] with narrow {{lichengloss|lobes}}, pale yellow powdery patches near the lobe edges, and an unusual chemical combination of [[lichexanthone]] in the upper layer and [[norstictic acid]] in the interior tissue.

==Taxonomy== ''Pyxine jolyana'' was [[species description|described]] as a new species in 2011 by Patrícia Jungbluth, [[Klaus Kalb]], and Marcelo Pinto Marcelli, based on material collected in [[São Paulo State]], Brazil. The [[botanical name|species epithet]] honors Carlos Alfredo Joly for his role in supporting [[biodiversity]] work in São Paulo State.<ref name="Jungbluth et al. 2011"/>

In overall appearance it resembles some other small-lobed, gray-brown members of ''[[Pyxine]]'', but it is set apart by its chemistry: it contains [[lichexanthone]] in the upper {{lichengloss|cortex}} and [[norstictic acid]] in the [[medulla (lichenology)|medulla]], a combination that is uncommon in South American members of the genus. It is also distinguished by its frequent, pale yellow [[soralia]] (the powdery structures that release [[soredia]]) and by the patchy yellow-to-salmon pigmentation that develops in the upper medulla, which can vary across the [[thallus]].<ref name="Jungbluth et al. 2011"/>

==Description== The thallus (lichen body) is tightly attached to its [[substrate (biology)|substrate]] and usually forms a roughly circular [[rosette (botany)|rosette]] up to about {{cvt|7|cm}} across. It is brownish gray and divided into narrow lobes ({{lichengloss|laciniae}}) about 0.5–1.0&nbsp;mm wide, with rounded to slightly squared-off tips. The upper surface is mostly smooth and lacks [[isidia]] or other solid vegetative outgrowths, but soralia are common and tend to sit just inside the lobe margins; the soredia are powdery to slightly granular. The lower surface is black (often a bit paler toward the lobe tips) and bears many {{lichengloss|simple}} (unbranched) [[rhizine]]s of similar color, reaching about 0.7&nbsp;mm long.<ref name="Jungbluth et al. 2011"/>

Internally, the medulla is variably colored: it may be cream to pale yellow to salmon in upper parts, and sulphur-yellow beneath soralia, while a thin lower layer can remain white. In older central areas a reddish-purple pigment reaction may appear with [[potassium hydroxide]] solution (the [[K test]]). [[Pycnidia]] are rare and occur on the upper surface; the conidia are small and flask-shaped. Chemically, the cortex contains lichexanthone (giving a yellow [[fluorescence]] under [[ultraviolet]] light), while the medulla contains norstictic acid along with [[triterpene]]s and pigments; the norstictic acid can be unevenly distributed, so spot tests from the lobe tips alone may miss it.<ref name="Jungbluth et al. 2011"/>

==Habitat and distribution== This species was originally known from São Paulo State in southeastern Brazil, with records from coastal and near-coastal localities (including [[Peruíbe]], [[Ubatuba]], and [[São Luís do Paraitinga]]). It occurs from near sea level (about 1–5&nbsp;m) up to at least {{cvt|915|m|-1}} elevation.<ref name="Jungbluth et al. 2011"/> It has since been recorded from [[Minas Gerais]].<ref name="Aptroot et al. 2022"/><ref name="Aptroot et al. 2025"/>

''Pyxine jolyana'' grows either on rock ([[saxicolous lichen|saxicolous]]) or on bark and woody surfaces ([[corticolous lichen|corticolous]]). Collections include thalli on coastal rocks, on palm stipes near a river mouth in windy, sun-exposed conditions, and on twigs and tree trunks at the edges of forest (including [[restinga]] vegetation near the ocean and shaded forest margins).<ref name="Jungbluth et al. 2011"/>

==References== <references>

<ref name="Aptroot et al. 2022">{{cite journal |first1=André |last1=Aptroot |first2=Maria Fernanda |last2=de Souza |first3=Marcela Eugenia da Silva |last3=Cáceres |first4=Lidiane Alves |last4=dos Santos |first5=Adriano Afonso |last5=Spielmann |year=2022 |title=New lichen records from Brazil |journal=Archive for Lichenology |volume=31 |page=44 |url=https://d-nb.info/1253929912/34}}</ref>

<ref name="Aptroot et al. 2025">{{cite journal |last1=Aptroot |first1=André |last2=da Silva Cáceres |first2=Marcela Eugenia |last3=dos Santos |first3=Lidiane Alves |last4=Benatti |first4=Michel N. |last5=Canêz |first5=Luciana |last6=Forno |first6=Manuela Dal |last7=Feuerstein |first7=Shirley C. |last8=Vidigal Fraga Junior |first8=Carlos Augusto |last9=Gerlach |first9=Alice C. L. |last10=Gumboski |first10=Emerson Luiz |last11=Jungbluth |first11=Patrícia |last12=Käffer |first12=Márcia I. |last13=Kalb |first13=Klaus |last14=Koch |first14=Natália M. |last15=Lücking |first15=Robert |last16=Torres |first16=Jean-Marc |last17=Spielmann |first17=Adriano A. |title=The Brazilian lichen checklist: 4,828 accepted taxa constitute a country-level world record |journal=The Bryologist |volume=128 |issue=2 |year=2025 |doi=10.1639/0007-2745-128.2.96 |pages=96–423 [292]}}</ref>

<ref name="CoL_4QYK3">{{Catalogue of Life |id=4QYK3 |title=''Pyxine jolyana'' Jungbluth, Kalb & Marcelli |access-date=28 January 2026}}</ref>

<ref name="Jungbluth et al. 2011">{{cite journal |last1=Jungbluth |first1=P. |last2=Marcelli |first2=P.M. |last3=Kalb |first3=K. |year=2011 |title=A new species and a new record of ''Pyxine'' (Physciaceae) with norstictic acid from São Paulo State, Brazil |journal=Mycotaxon |volume=115 |pages=435–442|doi=10.5248/115.435 |doi-access=free}}</ref>

</references>

{{Taxonbar|from=Q78391050}}

[[Category:Pyxine|jolyana]] [[Category:Lichen species]] [[Category:Lichens described in 2011]] [[Category:Lichens of Brazil]] [[Category:Taxa named by Klaus Kalb]]