{{Short description|Species of lichen}} {{Use dmy dates|date=June 2023}} {{Speciesbox | image = | image_caption = | taxon = Diorygma cameroonense | authority = [[Klaus Kalb|Kalb]] (2020) }}

'''''Diorygma cameroonense''''' is a little-known species of [[corticolous lichen|corticolous]] (bark-dwelling) [[script lichen]] in the family [[Graphidaceae]].<ref name="CoL"/> It is found in the pristine [[rainforest]]s of eastern [[Cameroon]]. This lichen is distinct due to its larger {{lichengloss|ascospores}} with more [[septum|septa]] compared to the closely related ''[[Diorygma sticticum]]''.

==Taxonomy==

''Diorygma cameroonense'' was [[species description|formally described]] as a new species in 2020 by German lichenologist [[Klaus Kalb]]. The [[botanical name|species name]], ''cameroonense'', refers to the country where it was collected. The [[type (biology)|type specimen]] was collected on 1 April 1999 in Bewala II Village near Ngatto, [[East Region (Cameroon)|East Province]], Cameroon, in a pristine rainforest along the [[Boumba River]].<ref name="Kalb 2020"/>

==Description==

The [[thallus]] of ''Diorygma cameroonense'' is corticolous, greenish-grey, and can reach up to {{convert|10|cm|in|abbr=on|0}} in diameter. It has a smooth to uneven surface and is 100–125&nbsp;[[micrometre|μm]] thick. The lichen's [[ascocarp|fruit bodies]] are in the form of {{lichengloss|lirellae}}, which are single, unbranched or stellately to irregularly branched, and immersed to {{lichengloss|erumpent}} with a thick, complete {{lichengloss|thalline margin}}. Ascospores are [[ellipsoid]] and somewhat {{lichengloss|muriform}}, measuring 15–20 by 5–8&nbsp;μm, with 3–5 transverse and 0–1 longitudinal [[septum|septa]] in 1 or 2 segments.<ref name="Kalb 2020"/>

The lichen contains three [[lichen product]]s: [[stictic acid]] (major), [[menegazziaic acid]] (minor), and [[constictic acid]] (submajor).<ref name="Kalb 2020"/>

===Similar species===

''Diorygma cameroonense'' is part of the genus ''[[Diorygma]]'', which includes other species with small ascospores, such as ''[[Diorygma |D.&nbsp;microsporum]]'' from Brazil, Colombia, and the United States (Florida); ''[[Diorygma pauciseptatum|D.&nbsp;pauciseptatum]]'' from Brazil; and ''[[Diorygma sticticum|D.&nbsp;sticticum]]'' from Thailand. ''Diorygma cameroonense'' is distinguished from these species by its larger and more septate ascospores, as well as its unique chemistry.<ref name="Kalb 2020"/>

==Habitat and distribution==

''Diorygma cameroonense'' is found in Cameroon, specifically in the East Province. It grows on the bark of trees in pristine rainforests along the Boumba River at an elevation of about {{convert|600|m|ft|abbr=on}}.<ref name="Kalb 2020"/>

==References== {{Reflist|refs=

<ref name="CoL">{{Catalogue of Life |id=B3BZC |title=''Diorygma cameroonense'' Kalb |access-date=11 June 2023}}</ref>

<ref name="Kalb 2020">{{cite journal |last1=Kalb |first1=K. |year=2020 |title=New or otherwise interesting lichens. VII, including a world key to the lichen genus ''Heiomasia'' |journal=Archive for Lichenology |volume=15 |pages=1–18 |url=http://www.fschumm.de/Archive/Vol15_Kalb_New_lichens_VII.pdf}}</ref>

}}

{{Taxonbar|from=Q107638473}}

[[Category:Diorygma|cameroonense]] [[Category:Lichen species]] [[Category:Lichens described in 2020]] [[Category:Lichens of Cameroon]] [[Category:Taxa named by Klaus Kalb]]