A new species of Hexacladia Ashmead (Hymenoptera, Encyrtidae) and new record of Hexacladia smithii Ashmead as parasitoids of Dichelops furcatus (Fabricius) (Hemiptera, Pentatomidae) in Argentina.

Pentatomid adults of the species Dichelops furcatus (F.), collected on stubble of soybean, Glycine max (Linnaeus) Merril, in Santa Fe province of Argentina, were found parasitized by two encyrtid wasp species (Hymenoptera: Encyrtidae). One of the encyrtids is described as Hexacladia dichelopsis Torréns & Fidalgo, sp. n., from both sexes, and the other species H. smithii Ashmead, is recorded for the first time from D. furcatus in Argentina. Both species are gregarious endoparasitoids which carry out the whole development (larval and pupal) in their living hosts; they emerge as imagoes, by cutting their way out through the dorsal wall of the abdomen. Including the newly described H. dichelopsis, seven species of the genus are recorded from South America, and an identification key to separate them is presented. [ABSTRACT FROM AUTHOR]