Megacopta cribraria ( F.) 299
in the spring of 2011 when a series of violent and active weather fronts moved through Alabama and
Georgia into South Carolina and North Carolina.
Only a few new confirmations of Megacopta cribraria were reported in 2014. Those were primar-
ily along the Gulf Coast and in the Mississippi River Valley. Leslie et al. (2014) reported that adults
overwintering under leaf litter and in crevices under pine tree bark at several locations in Maryland did
not survive two severe freezing events of temperatures as low as -12 to -15 °C in January 2014. Even in
central Georgia, January 2014 temperatures dipped to -10 °C six times, -12 °C two times, and -14 °C one
time (Georgia Automated Environmental Monitoring Network 2015). Winter mortality, therefore, might
account for the lower numbers of bugs in 2014 than had been observed in previous years in many areas
of the insect’s distribution. It also might account for the fewer numbers of new confirmations reported in
- There were again only a few new counties added to the known distribution in 2015 and 2016; these
were primarily west and south of the previous distribution records.
5.4 General Biology
5.4.1 Life Cycle
Zhang et al. (2012) provided basic information on the life cycle of Megacopta cribraria in the southeast-
ern United States. There were two peaks in oviposition, April to early June and July to August, suggest-
ing two generations per year. This appears to be the case across the southeastern United States although
the appearance in spring may be later further north and earlier in the south. In Florida, we have found
few eggs deposited on kudzu after August even though the plant may be active through December. Two
generations per year also were reported by Li et al. (2004) in China, and Tayutivutikul and Kusigemati
(1992b) in Japan, whereas Wang et al. (1996) and Wu et al. (2006) stated there are three generations in
Zhejiang and Fujian, China, respectively.
Reported longevity of adults has been quite variable. Ramakrishna Aiyar (1913) and Srinivasaperumal
et al. (1992) reported that longevity is relatively short at 2–5 days and 7 days, respectively. On the other
hand, Thippeswamy and Rajagopal (2005a,b) and Zhang et al. (2012) reported ranges in adult longev-
ity of 23–77, 25–43, and 6–25 days, respectively, which was influenced by host plant. Ruberson et al.
(2013) observed longevity of 21–43 days when the bugs were held in a laboratory on pods of snap beans,
Phaseolus vulgaris L. (Fabaceae).
As with most other pentatomoids, Megacopta cribraria deposits its eggs in masses, but the eggs
are typically laid in two or, rarely, three rows (Figure 5.1A). The eggs are elongate, about 0.86 mm
long, with longitudinal ridges and an operculum that is surrounded by a number of spinose projections
(Zhang et al. 2012). They have been described or figured by Kershaw (1910), Moizuddin and Ahmad
(1979), Ren (1984, 1992), Zhang et al. (2012), and Leslie et al. (2014). They are not deposited upright
as in most other pentatomoids but are arranged on their sides with the operculum facing out. This
may be an adaptation to facilitate access to the symbiont capsules, which are deposited underneath
the two rows of eggs (Figure 5.1B) (see Section 5.4.4, Endosymbionts, for further discussion). Eggs
usually are deposited on new leaf sheaths but may also be found on the undersides of older leaves or
on stems. Tayutivutikul and Kusigemati (1992b) found that most of the eggs were found in the upper
strata of the plant, whereas adults and nymphs were found in the middle to upper strata. Egg masses
were reported to contain an average of 15.64 eggs in the southeastern United States (Zhang et al.
2012), 12–38 eggs in Pakistan (Ahmad and Moizuddin 1977), and an average of 31.7 eggs in Japan
(Tayutivutikul and Kusigemati 1992b). Females deposited an average total of 96.5 eggs on soybean
and 102.6 on lablab or field bean [Lablab purpureus (L.) Sweet] (Fabaceae) in India (Thippeswamy
and Rajagopal 2005a), 78–274 on lablab bean in India and an average of 102 on lablab bean in Pakistan
(Ahmad and Moizuddin 1977), but only 26–29 on kudzu in Japan (Tayutivutikul and Yano 1990).
Shi et al. (2014) reported a range of 49 to 160 eggs depending on temperature. Ramakrishna Aiyar
(1913) reported 10–40 eggs per female, but it is not clear if this is the number per egg mass or the total
number of eggs deposited. Duration of the egg stage was about 6–7 days in India (Ramakrishna Aiyar
1913, Thippeswamy and Rajagopal 2005b) and 4–12 days in Pakistan (Ahmad and Moizuddin 1977).