Bagrada hilaris (Burmeister) 231
(Platygastridae), and Ooencyrtus sp. (Encyrtidae). There is no biological information on G. goniko-
palense or Ooencyrtus sp., but the adult and larval morphology, biology, and behavior of T. hyalinipennis
on B. hilaris in India were published by Subba Rao and Chacko (1961) (as Allophanurus indicus n. sp.).
This is the first record of an Ooencyrtus sp. attacking B. hilaris. Host specificity testing for all three
parasitoids was initiated in 2015. Further exploration is planned for southern Africa.
3.7 Future Outlook
As one of our most recent invasive pentatomoids in North America, the full ecological and economic
impacts of Bagrada hilaris are difficult to predict. Based on its rapid establishment and geographic
expansion, this stink bug clearly has adjusted well to conditions in western North America; it quickly
has become an economic pest of brassicaceous crops in all regions it has invaded. With the broad
geographic distribution of brassicaceous hosts in North America, the limiting factors to the spread of
B. hilaris likely will be environmental (e.g., temperature, moisture, and humidity). Currently, studies
are underway to use these parameters and host availability to predict the likely distribution and risk of
this bug moving into new areas (M. Papes and T.M. Perring, unpublished data). Of course, various life
history parameters and thermal requirements of this stink bug may change as it adapts to new biotic
and abiotic conditions.
Much work remains in developing effective conventional and organic IPM strategies for this
pest. Although the literature on its host plants clearly shows that the bugs prefer members of the
Brassicacaeae, non-related crops such as corn, melon, pepper, potato, and wheat are feeding hosts
that have experienced economic losses. A better understanding of the interactions of Bagrada hilaris
with other species, particularly weeds and native plants, will be important considerations for manage-
ment. These landscape level interactions among potential hosts need to be evaluated. Conventional
insecticide use likely will continue to remain high on cole crops under attack by the B. hilaris until
other management methods become more effective at suppressing its populations. Organic methods
of management may prove to be particularly problematic due to limited management options. Also,
more research is needed on effective biological control agents for this insect. The unique ovipositional
behavior of B. hilaris effectively reduces the success of native pentatomid egg parasitoids and preda-
tors that exist in North America. Thus, of critical importance is the search and importation of natural
enemies that have adapted to this bug in its native environment and the evaluation of native predators
targeting prey in the soil.
3.8 Acknowledgments
We thank J. E. McPherson (Department of Zoology, Southern Illinois University, Carbondale) for
his tireless efforts in the final editing of this chapter, David. A. Rider (Department of Entomology,
North Dakota State University, Fargo) for developing the synonymy list used in this chapter, Sergio R.
Sanchez-Peña and Ivonne Torres (Universidad Autónoma Agraria Antonio Narro, Mexico), for providing
data on current distribution of Bagrada hilaris in Mexico, Gevork Arakelian (Department of Weights
and Measures, South Gate, CA) for information on the early interception of B. hilaris in California,
Frederic J. Klicka (Southwest Ag Service, Inc., Brawley, CA) for providing information on the efficacy
of row covers for B. hilaris management, Timothy R. Lewis (Department of Entomology, University
of California, Riverside) for generating the North American distribution map for B. hilaris, Jocelyn G.
Millar (Department of Entomology, University of California, Riverside) for providing data on poten-
tial pheromones for B. hilaris, Darcy E. Oishi (Hawaii Department of Agriculture, Aiea) for provid-
ing information on the first report of B. hilaris in Hawaii, Elijah J. Talamas (USDA-ARS, Systematic
Entomology Laboratory, National Museum of Natural History, Washington, D.C.) for identification of
parasitoids, Raul T. Villanueva (Texas Agrilife Extension, Weslaco) for verification of central Texas
records of B. hilaris, and Keloth Rajmohana (Zoological Survey of India, Calicut) for identification of
parasitoids and for checking Indian parasitoid records.