Descriptions and a key are provided for 7 South American species of Note rap ion Kissinger (2002) (type species Apion meorrhynchum Philippi and Philippi) including N. bruchi (Beguin-Billecocq), N. meorrhynchum (Philippi and Philippi), N. philippianum (Alonso-Zarazaga) and four new species described from Chile: N. chilense Kissinger, N. lwscheli Kissinger, N. nothofagi Kissinger, and N. saperion Kissinger. A lectotype designation is published for Apion meorrhynchum Philippi and Philippi and Apion uestitum Philippi and Philippi. Apion fuegianum Enderlein and A. pingue Beguin-Billecocq are synonymized with N. meorrhynchum (Philippi and Philippi), new synonymy. Noterapionini (new tribe) is erected for Noterapion Kissinger (type genus) within Apioninae. Extension of a phylogenetic analysis of Brentidae s. lato by Wanat (2001) places Noterapion near the base of Apioninae and shows the genus sharing various symplesiomorphies with primitive apionid subfamilies from Africa and not found otherwise in the New World apionids.
The weevils are associated with the southern beech, Nothofagus Blume (in Nothofagaceae, see Manos, 1997), also known from the Australasian Region. Noterapion meorrhynchum develops in abandoned cynipid wasp leaf galls. The combination of a plant host with biogeographic significance and the possession of very primitive characters suggests that Noterapion may represent an ancient lineage dating back to the time of the Cretaceous and the breakup of Gondwana
