The new species Amplistroma longicollis is described. It is characterized by pale to dark brown stromata covered with white mucilaginous exudates and rostrate long-necked perithecia, which also present mucilaginous exudates at the base. Its relationship with other species of the genera Amplistroma in the Amplistromataceae is studied with morphological, cultural and molecular sequence data of large subunit ribosomal DNA (28S rDNA) and elongation factor 1-alpha gene (ef1-alpha).