Thelotrema lepadinum

Thelotrema lepadinum
Scientific classification
Kingdom:	Fungi
Division:	Ascomycota
Class:	Lecanoromycetes
Order:	Graphidales
Family:	Graphidaceae
Genus:	Thelotrema
Species:	T. lepadinum
Binomial name
	Thelotrema lepadinum; (Ach.) Ach. (1803)
Synonyms
	List Lichen lepadinus Ach. (1799) ; Lichen opegraphus * lepadinum (Ach.) Lam. (1813) ; Endocarpon lepadinum (Ach.) Wahlenb. (1826) ; Pertusaria lepadina (Ach.) Hornem. (1837) ; Parmelia lepadina (Ach.) Hornem. (1837) ; Volvaria lepadina (Ach.) A.Massal. (1852) ; Antrocarpum lepadinum (Ach.) Trevis. (1852) ; Urceolaria lepadina (Ach.) Tuck. ex Curtis (1867) ; Lichen inclusus Sowerby (1800) ; Thelotrema lepadinum var. inclusum (Sowerby) Ach. (1803) ; Thelotrema inclusum (Sowerby) Funck (1808) ; Antrocarpum inclusum (Sowerby) Spreng. (1827) ; Thelotrema lepadinum var. scutelliforme Ach. (1810) ; Lichen opegraphus var. scutelliforme (Ach.) Lam. (1813) ; Endocarpon lepadinum var. scutelliforme (Ach.) Wahlenb. (1826) ; Thelotrema lepadinum var. rupestre Turner (1839) ; Thelotrema lepadinum f. rupestre (Turner) Cromb. (1894) ; Thelotrema obconicum Räsänen (1949) ; Thelotrematomyces lepadini E.A.Thomas ex Cif. & Tomas. (1954) ;

Thelotrema lepadinum is a species of crustose lichen in the family Graphidaceae. Commonly known as bark barnacles, it forms a greyish crust on tree bark, dotted with numerous small, urn-shaped fruiting bodies that have distinctive white-rimmed openings. The lichen is found worldwide on smooth-barked deciduous trees, and in Europe it serves as an indicator of ancient woodland due to its preference for long-undisturbed forests. First described by the Swedish lichenologist Erik Acharius in 1799, the species has been reclassified multiple times throughout its taxonomic history.