Euphorbia peruviandina, a New Species of subg. Chamaesyce sect. Anisophyllum from Central Peru, and Treatments of Two Related Andean Species

The new species Euphorbia peruviandina (Euphorbiaceae) is described and illustrated with photos and line drawings. It belongs to subgenus Chamaesyce section Anisophyllum and is restricted to the puna vegetation of central and southern Peru at elevations of 3300 to 4200 m. It is proposed to be endangered following IUCN criteria. A comparison is made with two other Andean species of the section, E. jamesonii of Ecuador and E. orbiculata of Colombia and Venezuela. For all three taxa, type specimens are cited, and morphological descriptions, habitat information, exsiccate, and synonymy are given. An identification key to these taxa is provided. Euphorbia melanocarpa is proposed to be a synonym of E. jamesonii, and E. meridensis is treated as a synonym of E. orbiculata.