Twelve species of Sticta are recorded from southern South America (Arg
entina and Chile including juan Fernandez) south of latitude 30-degree
s-S, viz., S. ainoae, S. caulescens, S. fuliginosa, S. gaudichaldia, S
. hypochra, S. hypopsila, S. lineariloba, S. limbata, S. longipes, S.
sublimbata and S. weigelii, and S. santessonii D. Galloway is newly de
scribed. A key is provided, and details of anatomy, morphology, distri
bution, ecology and taxonomy are discussed.