Pseudochakura (Hymenoptera: Eucharitidae), a New World genus of chalcidoids parasitic on ants

Abstract. The genus Pseudochakura Ashmead (Eucharitidae: Eucharitinae) is revised to include thirteen species which all share the complete fusion of the genae behind the mandibles and a loss of functional mouthparts. Eight Neotropical and one Nearctic species of Pseudochakura are described as new: atra (Mexico), condylus (lesser Antilles), excruciata (Brazil), frustrata (Argentina), liburna (Florida, U.S.A.), pauca (Argentina), prolata (Argentina), sculpturata (Brazil; Florida, U.S.A.), septuosa (Mexico). P. chilensis Kieffer is redescribed. The known distribution of P.nigrocyanea Ashmead is extended to Uruguay and Venezuela. The known distribution of P. americana (Howard) comb.n.] is extended to Panama, Columbia, Ecuador, Argentina and northward into the southern tip of Florida. All three previously described Nearctic species are synonomized under the name P.gibbosa (Provancher) with P.arizonensis (Crawford) and P.californica (Ashmead) as junior synonyms. Biological information is summarized providing new information on both plant and ant hosts. A phylogenetic hypothesis for the genus is nresenteri.