Megacopta cribraria ( F.) 315
Preventing Megacopta cribraria from entering structures may be important, although reports of it
doing so are not common; the insect primarily is a nuisance pest outside. Property owners should ensure
that screen is placed over possible routes of entry into the home; that screens on windows are well-seated;
and that soffit, ridge, and gable vents are screened properly. In locations where screening cannot be used,
steel wool can be inserted into these openings to prevent the entry of the bugs. Lastly, doors should have
a tight seal when closed, and doorsweeps should be installed.
The nuisance aspect of pests in the suburban environment often drives client complaints, especially
with seasonal pests, such as Megacopta cribraria, where pest numbers can be overwhelming. A pest
management company’s most common response to these complaints is the use of insecticide sprays,
typically those that result in rapid knockdown, to quickly eliminate the source of the nuisance when
applied directly (topical treatment) to resting insects on structures. It also is desirable, from both the pest
management company’s perspective (to reduce the number of return visits) and the client’s perspective
(to eliminate the nuisance), that a product remain active over time and that it continue to provide rapid
knockdown of subsequently invading insects that may be attracted to and land on previously-treated
surfaces. Products that provide quick knockdown of M. cribraria are more desirable than those that
allow insects to maintain their visibility, and thus nuisance status, even though they might eventually die
after an extended exposure. Repeat applications may be necessary, however, because kudzu and other
surrounding vegetation remain as a source of re-infestation. To reduce the frequency of re-application,
longer-lasting formulations such as microencapsulated and wettable powder products should be used, if
possible. Any formulation used should first be tested in a small area to be sure it does not stain, leave
unsightly residues, or negatively impact the treated surface. Rather than use insecticides indoors for
control of M. cribraria, insects that have entered the home should be vacuumed and the bagged insects
then placed in hot, soapy water.
In a large laboratory study, Seiter et al. (2013b) screened nine professional pest control insecticide
products (highest labeled rate for perimeter pest control) containing indoxacarb, pyrethroid, neonic-
otinoid, or pyrethroid + neonicotinoid mixtures, on five surfaces typically found on and around homes
(metal, vinyl, painted and unpainted wood, and brick) for their residual efficacy (1, 7, 16, and 30-day-
old residual) against adult Megacopta cribraria. In general, pyrethroid, neonicotinoid, and pyrethroid +
neonicotinoid mixtures were effective at killing M. cribraria adults in 2-hour long forced-exposure
experiments; products were faster acting on metal and vinyl than on pine plywood (latex-painted or
unpainted) and brick.
In the laboratory (Dan R. Suiter, unpublished data), wild adults of Megacopta cribraria collected on
kudzu in the fall were confined for 1-, 15-, or 60-minutes on small lengths of metal downspout treated
with labeled rates of dinotefuran or cyfluthrin, and aged for one day. The bugs were then placed in clean,
dry Petri dishes (no food or water). Mortality was recorded 1, 2, 24, and 48 hours following initiation of
the assay. After exposure for 1 minute, mortality of bugs exposed to dinotefuran ranged from 33 to 90%
after 1 and 2 hours, whereas mortality after 24 hours was 95 to 100%. After 1 and 2 hours, cyfluthrin
had killed 0% and 10% of bugs, with just 15% and 20% mortality after 24 and 48 hours. One hour fol-
lowing initiation of a 15- or 60-minute exposure, mortality of bugs exposed to either rate of dinotefuran
was 100%. Following a 15-minute exposure, cyfluthrin resulted in no mortality after 1 hour and just 20%
after 48 hours. Mortality following a 60-minute exposure to cyfluthrin was 41.7, 98.3, and 100%; after 1,
2, and 24 hours, respectively.
These laboratory results were supported by an October 2013 field study (Dan R. Suiter, unpublished
data) designed to evaluate the effectiveness of dinotefuran (0.10% or 0.30%) or a mixture containing
0.075% imidacloprid and beta-cyfluthrin against Megacopta cribraria when applied under simulated
field conditions to white, metal downspouts. Ninety-one-cm lengths of metal downspout were treated to
the point of runoff, allowed to air dry, and then suspended vertically above a 19 liter bucket containing
soapy water.
For all 16 sampling dates, the mean number of these bugs collected from buckets placed under
imidacloprid/cyfluthrin-treated gutters was not significantly different (P ≥ .05) from the mean number
collected from buckets under untreated gutters. On 13 of 16 sampling dates, the mean number of bugs
collected from buckets placed under a dinotefuran-treated gutter was significantly greater than the
mean number of bugs collected from buckets placed under untreated or imidacloprid/cyfluthrin-treated