The First Record of Ooencyrtus nezarae (Hymenoptera: Encyrtidae) on Kudzu Bug (Hemiptera: Plataspidae) in North America

Abstract

The kudzu bug, Megacopta cribraria (F.) (Heteroptera: Plataspidae), is an invasive insect pest introduced from Asia in 2009 that poses a threat to soybeans (Glycine max [L.] Merr. [Fabales: Fabaceae]) and other legume crops in the United States. Initially discovered in Georgia, M. cribraria rapidly expanded across the southeast until 2014 when a significant decline in its population was observed across many locations. This notable decline in M. cribraria populations is attributed to the emergence of new parasitoids and pathogens in its new invasive range. So far, only a single egg parasitoid, Paratelenomus saccharalis (Dodd) (Hymenoptera: Platygastridae), is known to parasitize the eggs of M. cribraria in the United States. Here, we report a new egg parasitoid of M. cribraria identified as Ooencyrtus nezarae Ishii, 1928 (Hymenoptera: Encyrtidae), recovered from egg masses of M. cribraria collected from soybean in Alabama. O. nezarae is reported to parasitize eggs from a variety of heteropteran families and has been observed parasitizing M. cribraria in China. To the best of our knowledge, this is the first report of O. nezarae in North America. The potentials of O. nezarae for biological control of M. cribraria in the United States and the direction of future studies are discussed.

Occurrence, Seasonal Abundance, and Superparasitism of Ooencyrtus kuvanae (Hymenoptera: Encyrtidae) as an Egg Parasitoid of the Spotted Lanternfly (Lycorma delicatula) in North America

“…In Michigan, a native solitary parasitoid, Atanycolus cappaerti Marsh and Strazanac (Hymenoptera: Braconidae), was found to be parasitizing 56%-71% of larvae of the invasive emerald ash borer Agrilus planipennis Fairmare (Coleoptera: Buprestidae) at one plot [56]. In Alabama, an average parasitism rate of 95.6% was observed at a single study plot for Ooencyrtus nezarae Ishii (Hymenoptera: Encyrtidae), a facultative gregarious egg parasitoid from Asia, on the kudzu bug (Megacopta cribraria (F.) (Hemiptera: Plataspidae)) [57]. More exposure of L. delicatula eggs to O. kuvanae over time in the field could result in higher parasitism in the future.…”

A fortuitous find: a unique haplotype of Ooencyrtus nezarae Ishii (Encyrtidae: Encyrtinae) discovered in Florida

“…It was later confirmed via correspondence with J.S. Noyes at The Natural History Museum, London, that this discrepancy could be explained by allometric scaling of funicular segments (Ademokoya et al 2018). The Alabama specimens were small (body length 0.70-0.77 mm) and the first two funicular segments of the female antenna were quadrate or slightly wider than long, in contrast to the descriptions of Ishii (1928) and Zhang et al (2005), which described them as longer than wide.…”

“…A. Dorsal habitus; B. Ventral habitus; C. Lateral habitus. Ademokoya et al (2018) noted that the Alabama population of O. nezarae exhibited differences in overall size and antennal morphometrics from the holotype. It was later confirmed via correspondence with J.S.…”

“…Laboratory reared specimens were compared to descriptions in Ishii (1928), Zhang et al (2005 and Ademokoya et al (2018). The morphology of the specimens was consistent with the diagnoses given in these references (see Figs 1, 2, 3): frontovertex approximately 1/3 of head width; ocelli forming an obtuse triangle; posterior ocelli closer to compound eye than to occipital margin; mandible with crenulated truncation and distal tooth; stigmal vein of wings longer than postmarginal vein; linea calva open posteriorly; dark colouration on coxae, mesal femora, sub-basal tibiae and apical tarsi; the rest of the legs whitish-yellow; body dark with bluish metallic sheen; reticulation present on most of body; apex of scutellum smooth.…”

“…Thus, egg parasitoids have the potential to arrive adventively in new areas. In addition to T. japonicus, three other species of hymenopteran egg parasitoid of pentatomoids have unexpectedly emerged in the United States within the last five years: T. hyalinipennis Rajmohana & Narendran, a parasitoid of Bagrada hilaris (Burmeister) (Pentatomidae), was discovered in California (Ganjisaffar et al 2018); Paratelenomus saccharalis, a specialist egg parasitoid of Megacopta cribraria, was detected in Georgia andFlorida (Gardner et al 2013, Medal et al 2015); and Ooencyrtus nezarae, a generalist egg parasitoid, was reared from M. cribraria in Alabama in 2016 (Ademokoya et al 2018).…”