Invasive Stink Bugs and Related Species (Pentatomoidea)

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228 Invasive Stink Bugs and Related Species (Pentatomoidea)


personal communication). However, members of the platygastrid genus Tiphodytes Bradley are egg para-
sitoids of water striders (Gerridae) rather than stink bugs.
Subba Rao and Chacko (1961) described Trissolcus hyalinipennis (as Allophanurus indicus) from
Bagrada hilaris (as B. cruciferarum) in India and recorded several details on its biology including ovi-
position behavior, adult and larval morphology, and development and reproduction. Ghosal (2006) noted
a range of 19–32 % egg parasitism in eastern India by a Trissolcus sp. The data apparently were collected
from eggs deposited on mustard plants.


3.6.3.2 Predators


Like most other free-living insects, pentatomids are reported to be attacked by a wide array of generalist
predators (McPherson and McPherson 2000). The earliest report of predation of Bagrada hilaris was by
domestic “fowls” in South Africa (Howard 1906). Also in South Africa, Gunn (1918) reported the redu-
viid Rhynocoris segmentarius (Germar) (as Harpactor segmentarius Germar) preying on nymphs and
adults and identified certain birds feeding on bugs infesting wheat. The only other report of predation on
B. hilaris was by a phoretic mite (Bochartia sp.) in India (Thaker et al. 1969).


3.6.3.3 Other Natural Enemies


There are numerous records of entomopathogens attacking pentatomids, and certain fungi have been
used in augmentation against pest species (e.g., Sosa-Gomez and Moscardi 1998, Rombach et al. 1986).
Gunn (1918) reported that Bagrada hilaris was killed by the fungus Isaria sp. during the South African
rainy season. Nematodes also regularly attack stink bugs (e.g., Esquivel 2011 and Stubbins et al. (2015)
as do parasitic flagellates (Gibbs 1957), but there are no reports of these natural enemies attacking
B. hilaris.


3.6.3.4 Native Natural Enemies


In the United States, four native natural enemies so far have been found attacking Bagrada hilaris in
New Mexico: a hymenopteran egg parasitoid, Ooencyrtus sp. (Tessa R. Grasswitz, personal observation);
the spined soldier bug, Podisus maculiventris (Say); the soft-winged flower beetle, Collops vittatus (Say);
and the spined assassin bug, Sinea diadema (F.). The three predatory species are widely distributed
in North America (Aldrich and Cantelo 1999, Voss and McPherson 2003, Eaton and Kaufman 2007,
Anonymous 2015), and, therefore, may be associated with B. hilaris in other parts of the United States
in addition to New Mexico.
Ooencyrtus sp. was recovered in New Mexico in large numbers in August 2013 when sheets of
Bagrada hilaris eggs from a laboratory colony were placed among infested host plants in the field for
7 days. Successful parasitism of these eggs indicates that there were no intrinsic physiological barriers
to parasitism by this species, but it remains to be determined if it will search for, and parasitize, eggs
deposited in the soil (which appear to be the preferred oviposition site under New Mexico conditions)
(Taylor, et al. 2014; Tessa R. Grasswitz, personal observations). In this respect, Narayanan et al. (1959)
noted that, in India, different species of parasitoids attacked Bagrada eggs laid on host plant leaves ver-
sus those deposited in the soil.
To help anticipate whether key egg parasitoids of native Pentatomidae might adapt to the eggs of
Bagrada hilaris, five species of common Platygastridae were colonized to determine if any would para-
sitize and develop in B. hilaris eggs (Walker A. Jones, unpublished data). Parasitoids used in no-choice
tests were: Trissolcus basalis ( Wol la ston), Trissolcus brochymenae (Ashmead), Trissolcus euschisti
(Ashmead), Trissolcus hullensis (Harrington), and Telenomus podisi Ashmead. T. brochymenae is the
most important parasitoid of the harlequin bug, Murgantia histrionica, the only other common North
American pentatomid in the same tribe (Strachiini) as B. hilaris. No native Trissolcus spp. accepted
B. hilaris eggs. However, a small proportion of exposed eggs were attacked successfully by T. podisi
females. T. podisi, along with all other studied platygastrid parasitoids of pentatomid eggs, have evolved
host finding cues that culminate in the location and selection of host eggs glued together in masses on

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