Xanthoria elegans

Xanthoria elegans
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Peltigerales
Order:	Teloschistales
Family:	Teloschistaceae
Genus:	Xanthoria
Species:	X. elegans
Binomial name
Xanthoria elegans (Link) Th.Fr. (1860)
Synonyms
Species synonymy Parmelia elegans (Link) Ach. (1803) Placodium elegans (Link) DC. (1805) Lecanora elegans (Link) Ach. (1810) Squamaria elegans (Link) Fée (1829) Physcia elegans (Link) de Not. (1847) Callopisma elegans (Link) Trevis. (1852) Teloschistes elegans (Link) Norman (1853) Amphiloma elegans (Link) Körb. (1855) Caloplaca elegans (Link) Th.Fr. (1871) Gasparrinia elegans (Link) Stein (1879) Rusavskia elegans (Link) S.Y.Kondr. & Kärnefelt (2003) Subspecies synonymy Caloplaca elegans f. abbrevians (Eitner) Zahlbr. 1931 Caloplaca elegans f. areolata (Harm.) Mereschk. 1920 Caloplaca elegans f. confusa (Wedd.) Zahlbr. 1931 Caloplaca elegans f. crenata (Cromb.) I.M. Lamb 1939 Caloplaca elegans f. discretula (Müll. Arg.) Zahlbr. 1931 Caloplaca elegans f. elegans (Link) Th. Fr. 1871 Caloplaca elegans f. farcta Th. Fr. 1902 Caloplaca elegans f. fulva (Schaer.) Zahlbr. 1931 Caloplaca elegans f. orbicularis (Schaer.) Zahlbr. 1931 Caloplaca elegans f. prolifera Grummann 1931 Caloplaca elegans f. sordidescens (Vain.) Zahlbr. 1931 Caloplaca elegans f. subvitellina Suza 1929 Caloplaca elegans f. tenuis (Wahlenb.) Oxner 1937 Caloplaca elegans var. athallina (F. Wilson) Zahlbr. 1931 Caloplaca elegans var. australis (Zahlbr.) Zahlbr. 1924 Caloplaca elegans var. bifrons (Müll. Arg.) Zahlbr. 1931 Caloplaca elegans var. brachyloba Zahlbr. 1908 Caloplaca elegans var. caespitosa Müll. Arg. 1878 Caloplaca elegans var. compacta Arnold Caloplaca elegans var. discopa Th. Fr. 1886 Caloplaca elegans var. discreta (Schaer.) Zahlbr. 1901 Caloplaca elegans var. ectaniza (Nyl.) Zahlbr. 1931 Caloplaca elegans var. elegans (Link) Th. Fr. 1871 Caloplaca elegans var. ferox (Müll. Arg.) Zahlbr. 1931 Caloplaca elegans var. gainii (Hue) Zahlbr. 1931 Caloplaca elegans var. granulosa (Schaer.) Th. Fr. 1871 Caloplaca elegans var. imbricata (Müll. Arg.) Jatta 1902 Caloplaca elegans var. laxa (Müll. Arg.) Jatta 1902 Caloplaca elegans var. lucens Nyl. Caloplaca elegans var. muscicola Jatta 1910 Caloplaca elegans var. pertenuis (Harm.) Lettau 1918 Caloplaca elegans var. pulvinata (C.W. Dodge & G.E. Baker) Js. Murray 1963 Caloplaca elegans var. subpapillifera (Vain.) Zahlbr. 1940 Caloplaca elegans var. subtubulosa Th. Fr. 1873 Caloplaca elegans var. tenuis (Wahlenb.) Th. Fr. 1871 Caloplaca elegans var. trachyphylla (Tuck.) Fink 1935 Caloplaca elegans var. typica Th. Fr. 1871

Xanthoria elegans, commonly known as the elegant sunburst lichen, is a lichenized species of fungus in the genus Xanthoria, family Teloschistaceae. Recognized by its bright orange or red pigmentation, this species grows on rocks, often near bird or rodent perches. It has a circumpolar and alpine distribution. It was one of the first lichens to be used for the rock-face dating method known as lichenometry.

Xanthoria elegans was described by Johann Heinrich Friedrich Link as Lichen elegans in 1791, and transferred to the genus Xanthoria by Theodor Magnus Fries (son of Elias Magnus Fries) in 1860.

The thallus of this lichen is described as foliose, having the aspect of leaves, although the central portions of the thallus may appear nearly crustose. It is small, typically less than 5 cm (2 in) wide, with lobes less than 2 mm (0.08 in) broad, appressed to loosely appressed. The upper surface is some shade of orange while the lower surface is white, corticate, with short, sparse hapters (an attachment structure produced by some lichens). The vegetative propagules called soredia and isidia are absent, although apothecia are common. It has been described as possessing swollen, orange-yellow thalli (in streams), compact orange thalli (on boulders) or dark orange-red thalli on the driest rock faces.

The variety X. elegans var. granulifera, characterized by having isidia-like vegetative propagules, has been reported from Greenland and Spitsbergen.

Xanthoria elegans was one of the first species used for lichenometry, a technique of estimating the age of rock faces by measuring the diameter of the lichen thalli growing on them. After an initial period of one or two decades to establish growth (the interval), X. elegans grows at a rate of 0.5 mm per year for the first century, before slowing down somewhat.

...
Wikipedia