May-July 1999, February-March 2000
The genera in the lichen family Teloschistaceae has for long been known to be very artificially delimited. Recent treatments, particularly of the genus Caloplaca, based on morphology and anatomy have not provided a better understanding of the evolution of characters in the family and the generic structure is still very unsatisfactory. Therefore Ulrik Søchting and Francois Lutzoni have cooperated on a phylogenetic study of particularly the generic boundary between the genera Caloplaca and Xanthoria based on molecular characters. In spring 1999 a Robert O. Bass grant to Ulrik Søchting made it possible for him to visit Francois Lutzoni at the Field Museum to perform phylogenetic analyses of sequences of the small and the large subunits of nuclear ribosomal DNA of Caloplaca and Xanthoria species.
The following winter Ulrik Søchting visited the Pritzker Laboratory at the Field Museum together with a technician for three weeks to sequence the large subunit and the ITS region of nuclear ribosomal DNA of the genera Caloplaca and Xanthoria. These studies focused particularly on Antarctic and Subantarctic clades of the family in order to provide a better understanding of the origin of the lichen flora of those regions.