Synapomorphic characters of Zethus (Zethastrum) indicated in Z. ceylonicus A habitus B labial palpus C propodeum and basal portion of petiole, posterior view; arrowhead indicates submedian carina; arrow indicates basal longitudinal carina in first tergum D third metasomal tergum, lateral view; arrow indicates confluent indent. Scale bars: 1.0 mm.

  Part of: Lopes RB, Carpenter JM, Noll FB (2021) Cladistic analysis of Zethus Fabricius, 1804 (Hymenoptera, Vespidae): a new subgeneric classification. Journal of Hymenoptera Research 82: 253-283.