Enchylium limosum

The species Enchylium limosum, commonly known as lime-loving tarpaper lichen, derives its name from its original classification as Collema limosum, attributed to the Swedish botanist Erik Acharius. The specific epithet "limosum" is derived from the Latin word "limosus", meaning "full of mud" or "slime", which aptly describes the dark, wet thallus characteristic of this lichen.Wilhelm, G. (2023). Lichens of the Southern Lake Michigan Region (dissertation). Conservation Research Institute, Michigan. Retrieved March 29, 2024, from [https://ia600206.us.archive.org/19/items/lichens_michigan/lichens_michigan.pdf PDF]{{Cite web |title=Lime-loving Tarpaper Lichen (Enchylium limosum) |url=https://inaturalist.ca/taxa/462862-Enchylium-limosum |access-date=2024-04-30 |website=iNaturalist Canada |language=en}}File:Swedish Lichens.jpg

Enchylium limosum was originally described by Swedish botanist Erik Acharius in 1799 under the name Lichen limosus in "Lichenogr. Suec. Prodr." Throughout its taxonomic history, E. limosum has undergone several changes in nomenclature.{{Cite journal |last1=Seaward |first1=Mark R.D. |last2=Richardson |first2=David H.S. |last3=Brodo |first3=Irwin M. |last4=Harris |first4=Richard C. |last5=Hawksworth |first5=David L. |date=2017 |title=Checklist of Lichen-forming, Lichenicolous and Allied Fungi of Eagle Hill and its Vicinity, Maine |url=https://www.jstor.org/stable/26453954 |journal=Northeastern Naturalist |volume=24 |issue=3 |pages=349–379 |doi=10.1656/045.024.0305 |jstor=26453954 |issn=1092-6194 }} Originally described by Ach. in 1799 as Lichen limosus, it was later reassigned by Ach. in 1810 as Collema limosum in "Lich. Univ."{{cite journal |last=GBIF Secretariat |date=2023 |title=Collema limosum (Ach.) Ach. in GBIF Secretariat |url=https://www.gbif.org/species/5260640 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}} Subsequent taxonomic revisions led to further adjustments, such as its classification as Collema glaucescens var. limosum by German lichenologist Julius von Flotow in 1850[https://www.gbif.org/species/211512782 Collema glaucescens var. limosum (Ach.) Flot.] in Royal Botanic Gardens, Kew (2023). Species Fungorum Plus. Checklist dataset https://doi.org/10.15468/ts7wsb accessed via GBIF.org on 2024-04-04. and Collema pulposum var. limosum by British lichenologist William Mudd in 1861.{{cite journal |last=GBIF Secretariat |date=2023 |title=Collema pulposum var. limosum (Ach.) Mudd in GBIF Secretariat |url=https://www.gbif.org/species/5477801 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}}

In 1891, German botanist Kuntze (1843–1907) identified it as Gabura limosa in "Revis. gen. pl.,"{{cite journal |last=GBIF Secretariat |date=2023 |title=Gabura limosa (Ach.) Kuntze in GBIF Secretariat |url=https://www.gbif.org/species/3423072 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}} followed by its recognition as Collema cheileum var. glaucescens by Russian lichenologist Elenkin in 1904.{{cite journal |last=GBIF Secretariat |date=2023 |title=Collema cheileum var. glaucescens (Hoffm.) Elenkin in GBIF Secretariat |url=https://www.gbif.org/species/10959790 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}} British lichenologist Arthur Reginald Horwood further reassigned it as Eucollema glaucescens in 1912.{{cite journal |last=GBIF Secretariat |date=2023 |title=Eucollema glaucescens (Hoffm.) Horw. in GBIF Secretariat |url=https://www.gbif.org/species/3423071 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}}

In 2013, Mónica Andrea García Otálora, Per Magnus Jørgensen, & Mats Wedin proposed its current accepted name, Enchylium limosum. This taxonomic revision was published in the journal "Fungal Diversity" in 2014.{{Cite journal |last1=Otálora |first1=Mónica A. G. |last2=Jørgensen |first2=Per M. |last3=Wedin |first3=Mats |date=2014-01-01 |title=A revised generic classification of the jelly lichens, Collemataceae |url=https://doi.org/10.1007/s13225-013-0266-1 |journal=Fungal Diversity |language=en |volume=64 |issue=1 |pages=275–293 |doi=10.1007/s13225-013-0266-1 |issn=1878-9129 |via=Springer}}

Enchylium limosum has undergone several taxonomic revisions, so it is found under a number of different names in scientific literature. These synonyms include Collema forissii Szatala, Collema glaucescens Hoffm., Collema viscosum A. Massal., Collema limosum (Ach.) Ach., Collema pulposum var. limosum (Ach.) Mudd, Eucollema glaucescens (Hoffm.) Horw., Gabura limosa (Ach.) Kuntze, Lichen crispus limosum (Ach.) Lam., Lichen limosus Ach., and Parmelia limosa (Ach.) Ach.{{cite journal |last1=Otálora |first1=P. M. |last2=Jørg. |first2=M. |last3=Wedin |last4=GBIF Secretariat |date=2023 |title=Enchylium limosum (Ach.) Otálora, P.M.Jørg. & Wedin in GBIF Secretariat |url=https://www.gbif.org/species/8671626 |access-date=2024-03-29 |website=Checklist dataset |via=GBIF.org |doi=10.15468/39omei}}

File:Enchylium limosum microscopic thallus.jpg view of an Enchylium limosum specimen captured in Kreis Reutlingen, Baden-Württemberg, Germany.]]

Enchylium limosum is a diminutive crustose to subfoliose lichen species that forms a delicate, gelatinous thallus ranging from 100 to 500 micrometers in thickness when fully hydrated.Nimis P.L., 2016. [https://italic.units.it/index.php?procedure=taxonpage&num=932 ITALIC – The Information System on Italian Lichens]. Version 7.0. University of Trieste, Dept. of Biology, (https://dryades.units.it/italic), accessed on 2024-03-25. All data are released under a CC BY-SA 4.0 licence.{{Cite book |url=https://lichenportal.org/portal/taxa/index.php?taxauthid=1&taxon=53524&clid=201 |title=Lichen flora of the greater Sonoran Desert region |date=2004 |publisher=Lichens Unlimited, Arizona State University |isbn=978-0-9716759-0-2 |editor-last=Nash |editor-first=Thomas H. |edition=2nd |location=Tempe, Ariz |pages=65–80}} The thallus has a distinctive dark olive-green to brownish-black coloration and a textural appearance that can vary from granulose to membranous. While the thalline margins are often indistinctly lobed, the lichen's vegetative structure is typically best developed in the areas surrounding the apothecia. E. limosum does not have an upper or a lower cortical layer.

The apothecia of E. limosum are profuse, lecanorine in structure, and sessile,{{cite journal |last1=Ramirez |first1=J. |last2=Watson |first2=K. |last3=McMillin |first3=L. |last4=Gjieli |first4=E. |last5=Sessa |first5=E. |date=2024 |title=Lime Loving Lichens |url=https://www.nybg.org/bsci/lichens/eln/lime_loving_lichens.htm |access-date=2024-03-29 |website=The New York Botanical Garden Herbarium, Occurrence dataset |publisher=The New York Botanical Garden |via=GBIF.org |doi=10.15468/6e8nje |version=1.66}} measuring 1 to 3 millimeters in diameter, occasionally reaching up to 4 millimeters. The apothecial disc displays a flat to convex topography, ranging in color from reddish-brown to dark brown-black, and is bordered by a thick, often verrucose or lobulate thalline margin. Microscopically, the thalline exciple is either ecorticate{{Efn|Not having a cortex.{{cite web|url=https://www.merriam-webster.com/dictionary/ecorticate|title=ecorticate definition|website=Merriam-Webster}}|group=note}} or only pseudocorticate in the basal regions, while the proper exciple is poorly developed, composed of euthyplectenchymatous (elongated) or, more rarely, subparaplectenchymatous hyphae, and reaches up to 40 micrometers in lateral width.

The hymenium of E. limosum is colorless, measuring 80 to 120 micrometers in height, and exhibits a positive reaction to iodine staining (I+ blue). The paraphyses are simple or sparsely branched in their upper portions, 1.5 to 2 micrometers thick at the mid-level, and terminate in clavate to subglobose apical cells that are 3 to 4.5 micrometers wide. The hypothecium{{Efn|The dense hyphal tissue beneath the hymenium.{{cite web|url=https://www.merriam-webster.com/dictionary/hymenium|title=hypothecium defination|website=Merriam-Webster}}|group=note}} ranges from colorless to pale yellow in appearance.

File:Ascospores of Enchylium limosum.jpg of Enchylium limosum.]]

The asci of E. limosum are cylindrical-clavate in shape, containing (2-) 4 spores, with a distinctly thickened apex and a downwardly projecting, deeply blue-staining (K/I+) tubular structure. The ascospores themselves are muriform or submuriform, possessing 3 to 5 transverse septa and 1 to 2 longitudinal septa, hyaline in color, and ellipsoid to subovoid in shape with obtuse to rarely subacute ends, measuring (20-) 25 to 35 (−40) micrometers in length and (8-) 10 to 15 (−17) micrometers in width. The ascospores of E. limosum are around 30 micrometers in length.Vince J. Giavarini, (2016). [http://www.habitas.org.uk/lichenireland/species.asp?item=18445 Enchylium limosum (Ach.) Otálora, P.M.Jørg. & Wedin]. [In] LichenIreland. National Museums Northern Ireland. Accessed on 2024-03-29.

Pycnidia, when present, are infrequent, either immersed or slightly projecting, appearing as small reddish dots, and produce straight, bacilliform conidia that are 4 to 6 micrometers long and 1 to 1.8 micrometers wide. The photobiont of E. limosum is a cyanobacterium, specifically Nostoc, with the cells arranged in elongated chains. All spot tests conducted on this lichen species yield negative results, and no secondary metabolites have been detected.

E. limosum is considered a diminutive lichen species, characterized by its crustose thallus that is often more developed in the areas surrounding the relatively large and conspicuous apothecia, which contain 4-spored asci.{{cite journal |last1=Malíček |first1=J |last2=Palice |first2=Z |last3=Bouda |first3=F |last4=Knudsen |first4=K |last5=Šoun |first5=J |last6=Vondrák |first6=J |last7=Novotný |first7=P |date=2024 |title=Enchylium limosum (Ach.) Otálora, P.M. Jørg. & Wedin |url=https://dalib.cz/en/taxon/info/Enchylium%20limosum |journal=Atlas českých lišejníků |publisher=Institute of Botany of the Czech Academy of Sciences}} E. limosum is recognized as a typical pioneer species, commonly colonizing bare, often calcareous soils, including anthropogenic habitats such as quarries and spoil heaps, though its presence in these areas is generally temporary.

Enchylium limosum does not contain any detectable lichen substances or secondary metabolites.{{Cite journal |last1=Cannon |first1=P. |last2=Otálora |first2=M.A.G. |last3=Košuthová |first3=A. |last4=Wedin |first4=A. |last5=Aptroot |first5=A. |last6=Coppins |first6=B. |last7=Simkin |first7=J. |date=2020 |title=Peltigerales: Collemataceae, including the genera Blennothallia, Callome, Collema, Enchylium, Epiphloea, Lathagrium, Leptogium, Pseudoleptogium, Rostania and Scytinium. |url=https://kew.iro.bl.uk/work/881b4e11-d30d-460e-8f40-1812587c18c3 |journal=Revisions of British and Irish Lichens |volume=2 |pages=3–16 |doi=10.34885/174 |via=KEW |doi-access=free}} E. limosum exhibits negative reactions to all standard spot tests.

The species is found on substrates with a relatively acidic pH, ranging from 3 to 4. This indicates that E. limosum favors growing on subacid to subneutral substrates, such as those found in moderately disturbed environments.

File:World DNI Solar-resource-map GlobalSolarAtlas World-Bank-Esmap-Solargis.png

In terms of solar irradiation, E. limosum prefers sites with plenty of diffuse light but limited direct solar exposure, scoring a 3 on the 5-point scale. This suggests the species avoids both extremely shaded and highly sun-exposed situations.

The aridity tolerance of E. limosum is classified as mesophytic, with a value of 3 on the 5-point scale. This indicates the species can thrive in habitats with moderate moisture levels, neither too dry nor too wet.

Regarding eutrophication, E. limosum is found in areas with weak to moderate levels of nutrient enrichment, scoring 2–3 on the 5-point scale. This implies the species can tolerate some degree of environmental pollution or nutrient deposition, but likely avoids heavily eutrophicated sites.

In terms of poleotolerance, E. limosum is classified as occurring in moderately disturbed areas, with a value of 2 on the 4-point scale. This suggests the species is not exclusively found in natural or undisturbed habitats but can also colonize semi-natural environments with some level of human activity.

Finally, the altitudinal distribution of E. limosum spans the montane belt (value of 3) and the submediterranean belt (value of 2). This indicates the species is adapted to grow in mid-elevation habitats, typically associated with deciduous Quercus-Carpinus forests and Fagus-dominated stands.

Enchylium limosum is a widely distributed lichen species with a holarctic range, occurring across temperate to boreal-montane regions of Europe, North America, Africa, and Asia.{{Cite journal |last1=Nimis |first1=Pier Luigi |last2=Hafellner |first2=Josef |last3=Roux |first3=Claude |last4=Clerc |first4=Philippe |last5=Mayrhofer |first5=Helmut |last6=Martellos |first6=Stefano |last7=Bilovitz |first7=Peter O. |date=2018-03-12 |title=The lichens of the Alps – an annotated checklist |url=https://dryades.units.it/lichalp/index.php?procedure=taxonpage&num=1749 |journal=MycoKeys |language=en |issue=31 |pages=1–634 |doi=10.3897/mycokeys.31.23568 |doi-access=free |issn=1314-4049 |pmc=5914158 |pmid=29706791}} Within Europe, the species has been recorded from a number of countries, including Italy, the United Kingdom, Ireland, the Czech Republic, Austria, Switzerland, and France. E. limosum and similar species thrive in environments where calcium-rich minerals are present, such as limestone or dolomitic rocks.Christensen, Steen. (2023). 2023 PA 11 LichensKriti. 11. 65–71. ([https://www.researchgate.net/profile/Steen-Christensen-3/publication/374422481_2023_PA_11_LichensKriti/links/651d5cbad717ef1293cc2b0a/2023-PA-11-LichensKriti.pdf?origin=publication_detail&_tp=eyJjb250ZXh0Ijp7ImZpcnN0UGFnZSI6InB1YmxpY2F0aW9uIiwicGFnZSI6InB1YmxpY2F0aW9uRG93bmxvYWQiLCJwcmV2aW91c1BhZ2UiOiJwdWJsaWNhdGlvbiJ9fQ pdf]){{Cite book |last1=Nimis |first1=P. L. |url=https://www.worldcat.org/title/974041826 |title=The lichens of Italy: a second annotated catalogue |last2=Nimis |first2=P. L. |date=2016 |publisher=EUT, Edizioni Università di Trieste |isbn=978-88-8303-754-2 |location=Trieste |page=740 |oclc=974041826}}

Regarding its specific distribution within Europe, E. limosum has been documented in the following regions and localities:

File:Wet state of Enchylium limosum.jpg of Department of Life Sciences, University of Trieste.]]Enchylium limosum have a limited distribution within Italy, with the majority of known populations located in the southern regions of the country. The species seems to thrive primarily in the montane and submediterranean belts, with isolated occurrences recorded in Calabria, Campania, and Sardinia.

In Calabria, a single population of E. limosum has been documented in the Tarsia al Lago locality, situated within the montane belt. Similarly, in the Campania region, the species has been found in the Monti di Castellammare area, which falls within the submediterranean ecological zone.

The island of Sardinia also plays host to a known occurrence of E. limosum, with a population recorded along the western coast near the town of Buggerru, again within the submediterranean belt.

In the United Kingdom and Ireland, the species is considered locally distributed but widely scattered, with records from damp clay soils and exposed, soft coastal cliff faces.

In the Czech Republic, E. limosum occurs abundantly throughout the country, with habitats being quarries, spoil heaps, and setting pits.

Outside of Europe, this lichen has been recorded in the Canadian provinces of British Columbia, Manitoba, Nova Scotia, Northwest Territories, Nunavut, Ontario, Prince Edward Island, and Quebec, as well as the U.S. state of Minnesota.{{Cite web |title=Lime-loving Tarpaper Lichen |url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.127817/Enchylium_limosum |access-date=25 March 2024 |website=NatureServe}} In the Canadian North, E. limosum has been documented in the Southern Arctic and Taiga Plains ecozones, typically growing on calcareous soils.{{Cite web |title=Enchylium limosum (Collema limosum) {{!}} NWT Species Search |url=https://www.gov.nt.ca/species-search/enchylium-limosum-collema-limosum |access-date=25 March 2024 |website=Government of Northwest Territories}}

Ecologically, Enchylium limosum is considered a typical pioneer species, commonly colonizing bare, often calcareous soils in disturbed habitats such as quarries, spoil heaps, and setting pits. However, its presence in these anthropogenic environments is generally temporary, as the lichen is quickly outcompeted by other vegetation.

Within its distribution range, E. limosum has been observed growing on a variety of substrates, including mineral, clay, and sandy soils, as well as on terricolous mosses and plant debris. The species appears to prefer substrates that are somewhat calcareous in nature. Altitudinally, it has been recorded from the mesomediterranean belt, where the potential vegetation is dominated by evergreen broad-leaved forests with Quercus ilex, up to the montane belt, where deciduous forests with Fagus sylvatica and closed coniferous forests with Picea abies are the predominant vegetation types. Despite its wide distribution, E. limosum is generally considered an overlooked and uncommon lichen species, particularly in the Alps region.

Enchylium limosum is completely absent from the alpine belt, subalpine belt, oromediterranean belt, Padanian area, and dry mediterranean belt. In the montane belt, the species is extremely rare, with only a few known populations. Enchylium limosum is also extremely rare in the submediterranean belt. The species is very rare in the humid submediterranean belt and the humid mediterranean belt, with just a handful of recorded occurrences in these regions.P.L. Nimis & S. Martellos, 2016: ITALIC – The Information System on Italian Lichens. Version 7.0. University of Trieste, Dept. of Biology, (https://dryades.units.it/italic), accessed on 2024-03-25. When not otherwise specified, all data and items are released under a CC BY-SA 4.0 licence. ([https://italic.units.it/index.php?procedure=downloaddata&id=932 CSV])

{{Further|Conservation status}}

The conservation status of the lichen species Enchylium limosum varies considerably across its known geographic range, with limited and sometimes conflicting assessments available.

At the global level, the species' conservation status has not been comprehensively evaluated, and it is currently listed as Not Ranked (GNR) by NatureServe.

In Canada, Enchylium limosum's status differs significantly between provinces and territories. According to NatureServe, it is considered Critically Imperiled (S1?) in Nova Scotia, Vulnerable (S3) in British Columbia and Ontario, and Unranked (SNR) in Prince Edward Island and Quebec. The species' status is also listed as Unresolved (SU) in Manitoba, Northwest Territories, and Nunavut.

In the Northwest Territories of Canada, the General Status Rank for E. limosum is Undetermined, with a status rank of SU, indicating that further inventory and assessment are required to determine its conservation status. E. limosum has been designated as S1 (Critically imperiled) by Atlantic Canada Conservation Data Centre.{{Cite web |title=Species Conservation Status Rank |url=http://accdc.com/webranks/PEnvas.htm |access-date=25 March 2024 |website=Atlantic Canada Conservation Data Centre}}

Across the border in the United States, the national status of Enchylium limosum is Unranked (NNR), and it is also Unranked (SNR) in the only state for which data is available, Minnesota. Minnesota Department of Natural Resources have listed E. limosum in their "Plant and Fungi watchlist" due the species' recent decline in the state.{{Cite web |title=Plant and fungi watchlist |url=https://www.dnr.state.mn.us/eco/mbs/plant-watchlist.html |access-date=25 March 2024 |website=Minnesota Department of Natural Resources |language=en}}

Conversely, in Great Britain, the species is assessed as Least Concern (LC) according to the NBN Atlas Partnership and the British Lichen Society, suggesting it is not currently considered a conservation priority in that region.{{Cite web |title=Enchylium limosum {{!}} The British Lichen Society |url=https://britishlichensociety.org.uk/resources/taxon-database/enchylium-limosum |access-date=25 March 2024 |website=British Lichen Society}}{{Cite web |title=Enchylium limosum {{!}} NBN Atlas |url=https://species.nbnatlas.org/species/BMSSYS0000045192#overview |access-date=25 March 2024 |website=National Biodiversity Network}}

According to the Finnish Biodiversity Information Facility, Enchylium limosum has been assessed for inclusion in the Red List of Finnish Species on multiple occasions.{{Cite web |title=Enchylium limosum {{!}} Status {{!}} Finnish Biodiversity Info Facility |url=https://laji.fi/en/taxon/MX.65641/endangerment |access-date=25 March 2024 |website=laji.fi |language=fi}} In the most recent assessment, conducted in 2019, the species was categorized as Vulnerable (VU).{{Cite web |title=Punaisen kirjan verkkopalvelu |trans-title=Red List of Finnish Species |url=https://punainenkirja.laji.fi/results/MX.65641 |access-date=25 March 2024 |website=punainenkirja}} The main criteria that led to this categorization were related to the species' small population size (D1).

The key threats identified for E. limosum in Finland include:

• Overgrowing of meadows and other open habitats (N)
• Construction and development on the land (R)
• Other known reasons (Muu)
• Threats caused by alien species (Vie)

Prior to the 2019 assessment, E. limosum had also been evaluated in previous Red List assessments for Finland:

In the 2010 Red List, the species was again categorized as Vulnerable (VU). However, in the earlier 2000 Red List assessment, E. limosum was listed as Not Evaluated (NE), indicating that a comprehensive conservation status evaluation had not been conducted at that time.

The 2019 Red List of Estonian lichens designates E. limosum as a Vulnerable (VU) species in the region.{{Cite journal |last1=Lõhmus |first1=Piret |last2=Marmor |first2=Liis |last3=Jüriado |first3=Inga |last4=Suija |first4=Ave |last5=Oja |first5=Ede |last6=Degtjarenko |first6=Polina |last7=Randlane |first7=Tiina |date=2019-07-29 |title=Red List of Estonian lichens: revision in 2019 |url=http://ojs.utlib.ee/index.php/FCE/article/view/fce.2019.56.07 |journal=Folia Cryptogamica Estonica |volume=56 |pages=63–76 |doi=10.12697/fce.2019.56.07 |issn=1736-7786|doi-access=free }} In the Czech Republic, E. limosum was previously categorized as Near Threatened (NT) by Institute of {{Interlanguage link|Botany of the Czech Academy of Sciences|lt=Botany of the Czech Academy of Sciences|cs|Botanický ústav Akademie věd České republiky|WD=}} . However, a more recent assessment has elevated the species to the Endangered (C3) category.

{{reflist|group=note}}

{{Reflist}}

{{Commons category|Enchylium limosum}}

{{Wikispecies|Enchylium limosum}}

• [http://www.ndsu.edu/pubweb/~esslinge/chcklst/chcklst7.htm#E {{aut|North American Lichen Checklist}}, Version (#20) 19 April 2015.]
• [http://www.indexfungorum.org/Names/NamesRecord.asp?RecordID=805678 Enchylium limosum] in [http://www.indexfungorum.org/ Index Fungorum.]

{{Taxonbar|from=Q23654345}}

Category:Least concern biota of Europe

Category:Lichen species

Category:Lichens described in 1799

Category:Lichens of Europe

Category:Peltigerales

Category:Taxa named by Erik Acharius