Identification of two leafminer parasitoids (Hymenoptera: Eulophidae), Neochrysocharis formosa and Proacrias sp. from Australia, with both showing thelytoky and infection by Rickettsia

Abstract

Liriomyza huidobrensis, L. sativae and L. trifolii are polyphagous agromyzid leafminers that have recently arrived in Australia, posing a threat to Australian vegetable and ornamental crops. Adventive and endemic hymenopteran parasitoids of agromyzid leafminers already present in Australia should assist in the management of these invasive agromyzid species. Neochrysocharis formosa (Hymenoptera: Eulophidae: Entedoninae) is an idiobiont endoparasitoid commonly attacking Liriomyza spp. in many countries, but it has not been formally identified in Australia. This study provides the first confirmed Australian record of N. formosa as well as an unidentified Proacrias species, another entedonine species. Females of both species were reared from several adventive and endemic agromyzid leafminers in southern Australia. Laboratory cultures of both species established the presence of thelytokous reproduction. DNA barcodes (5′ COI, 3′ COI, ITS1, ITS2, 28S) were used to delineate species boundaries, with the 5′ end of the mitochondrial COI sequences pointing to multiple cryptic lineages among N. formosa. Additionally, 16S rRNA sequencing indicated that both species were infected with a Rickettsia bacterium, which is related to the Rickettsia present in thelytokous populations of N. formosa in Japan and China. These findings expand records for parasitoids attacking leafminers in Australia and highlight the potential for an endosymbiont to produce thelytokous strains that could provide for more efficient biocontrol agents for augmentative release.