Lecidea tessellata
{{Short description|Species of lichen}}
{{Use dmy dates|date=March 2023}}
{{Speciesbox
| image = Lecidea tessellata - Flickr - pellaea.jpg
| image_caption =
| taxon = Lecidea tessellata
| authority = Flörke (1819)
| synonyms = *Lecidea contigua var. tessellata {{au|(Flörke) Nyl. (1855)}}
- Lecidea lapicida *** tessellata {{au|(Flörke) Nyl. (1861)}}
- Lecidella tessellata {{au|(Flörke) Arnold (1880)}}
- Psora tessellata {{au|(Flörke) A.Massal. (1852)}}
}}
Lecidea tessellata is a species of saxicolous (rock-dwelling), crustose lichen in the family Lecideaceae. It was formally described as a species in 1819 by German botanist Heinrich Flörke. In northern North America, it is common and widely distributed, growing on non-calcareous rocks. It also occurs in Afghanistan, China, Nepal, Europe, and Russian Asia. In India, it has been recorded only from the alpine Western Himalayas at an altitude of {{convert|3450|m|ft|abbr=on}}. Its southern distribution extends to James Ross Island, where it is locally common.
Description
Lecidea tessellata has a chalky white to grey, cracked and areolate thallus. Its apothecia are black, subimmersed, appressed to adnate and range from 0.5 to 1.8 (–2.0) mm in diameter. The apothecial {{lichengloss|disc}} is smooth, initially rounded in young apothecia, but becomes convex and irregular in mature ones, sometimes with a thin white pruinose layer. The {{lichengloss|epihymenium}} is brownish-green to blackish-green and the {{lichengloss|hymenium}} is colorless, measuring 40–60 μm in height. The {{lichengloss|hypothecium}} is pale brown and measures 30–40 μm in height, while the {{lichengloss|excipulum}} is blackish-green externally and colorless internally. The {{lichengloss|asci}} are clavate and measure 30–50 by 8–14 μm, and the ascospores are ellipsoid and measure 7–9 by 5–6 μm. Lecidea tessellata contains confluentic acid, a lichen product that can be detected using thin-layer chromatography. Both the thallus and medulla of the lichen have negative reactions with standard chemical spot tests (K−, C−, PD−).
Lecidea oreophila, found in the mountains of California's Sierra Nevada, is similar in appearance to L. tessellata, but it has a dark hypothecium and produces 2′-O-methylmicrophyllinic acid as the primary lichen product, with or without accessory confluentic acid.
See also
References
{{Reflist|refs=
{{Catalogue of Life |id=3SV3Q |title=Lecidea tessellata Flörke |access-date=15 March 2023}}
{{cite web |title=Synonymy. Current Name: Lecidea tessellata Flörke, Deutsche Lich. 4: 5 (no. 64) (1819) |url=https://www.speciesfungorum.org/Names/SynSpecies.asp?RecordID=392664 |publisher=Species Fungorum |access-date=15 March 2023}}
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{{Taxonbar|from=Q10556093}}
Category:Lichens described in 1819
Category:Taxa named by Heinrich Gustav Flörke