Six new apotheciate species of Sticta (lichenized Ascomycota: Lobariaceae) from the Colombian Andes

As part of a phylogenetic and taxonomic revision of the lichenized genus Sticta in Colombia, six new species with apotheciate thalli but lacking vegetative propagules are described: Sticta atroandensis Moncada & Lucking sp. nov., S. brevior Moncada & Lucking sp. nov., S. lumbschiana Moncada & Lucking sp. nov., S. macrocyphellata Moncada & Coca sp. nov., S. parahumboldtii Moncada & Lucking sp. nov., and S. pseudohumboldtii Moncada & Lucking sp. nov. The last two are related to S. humboldtii but phylogenetically distinct and differ in details of cyphellae morphology and spot reactions. Sticta atroandensis is similar to S. andensis but has a dark lower tomentum, whereas S. brevior belongs in the S. kunthii group, being characterized by mainly laminal apothecia with tomentose margins and a rather stout thallus. Both S. lumbschiana and S. macrocyphellata form part of the S. dilatata group and can be characterized by their lobe surface structure and cyphellae anatomy. Keys to species of the S. dilatata and S. humboldtii groups are presented.