A new species of potter wasp from South America, Ancistrocerus
sur
sp. n., is described. A species key and checklist for all described Ancistrocerus that occur south of the Rio Grande are provided. New synonymy includes Odynerus
bolivianus Brèthes = Ancistrocerus
pilosus (de Saussure), while the subspecies bustamente
discopictus Bequaert, lineativentris
kamloopsensis Bequaert, lineativentris
sinopis Bohart, tuberculocephalussutterianus (de Saussure), and pilosus
ecuadorianus Bertoni, are all sunk under their respective nominotypical taxa.