A new species of Lepraria (Lecanorales: Stereocaulaceae) from the Canary Islands and the typification of Lepraria isidiata

The new species Lepraria santosii Argüello & Crespo is described from the Canary Islands. It is characterized by a crustose to subsquamulose thallus with slightly raised rim and the presence of atranorin and the stictic acid chemosyndrome. It is currently known from Tenerife (Canary Islands), where it grows on soil over basaltic rocks in the laurel forest. Twelve new sequences of the ITS region from this species and L. isidiata were obtained and analysed with sequences downloaded from GenBank. Maximum parsimony and Bayesian analyses suggest that Lepraria santosii is closely related to L. isidiata. The latter name is here lectotypified and the characters for the distinction of the two species from similar taxa are discussed.