Invasive Stink Bugs and Related Species (Pentatomoidea)

296 Invasive Stink Bugs and Related Species (Pentatomoidea)

on which to separate populations of M. cribraria into different species or even subspecies. Hosokawa
et al. (2014) analyzed mtDNA sequences for populations of this species from China, the southeastern
United States, and Japanese islands. Using a Bayesian phylogenetic analysis, they found that neither
‘M. cribraria’ nor ‘M. punctatissima’ was monophyletic, being represented by eight different clades. Their
conclusion that “neither M. cribraria nor M. punctatissima constitutes a monophyletic group, favoring
the idea that M. cribraria and M. punctatissima do not constitute distinct species but rather represent
local populations of the same species with considerable genetic and phenotypic diversity,” supports the
morphological conclusion that a single variable species, M. cribraria, is involved rather than two species.
Adults of Megacopta cribraria are small round bugs, 3.5 to 6.0 mm long, and light brown or olive to
dark brown in color with darker punctation (Figure 5.1E). Eger et al. (2010) provided a key to families of
Pentatomoidea from America north of Mexico. The combination of an enlarged scutellum covering most
of the abdomen and two-segmented tarsi separate this bug from all others in this geography. Among
North American bugs with the scutellum enlarged and covering most of the abdomen, M. cribraria can
be recognized easily by the broadly rounded to truncate posterior of the scutellum, which is narrowly
rounded in native species. Nymphs are yellow-brown, or greenish-yellow to olive-brown, relatively flat-
tened, and moderately to strongly setose (Figure 5.1C-D).

ABC

DE

G H

F

FIGURE 5.1 (See color insert.) Megacopta cribraria. A, egg mass; B, underside of egg mass, arrows indicate symbi-
ont capsules; C, second instar; D, fourth instar; E, adult female (Courtesy of Joe E. Eger); F, adults on gutter downspout;
G adults on side of house, Hoschton, GA (Courtesy of Dan R. Suiter); H, infestation of adults on young soybean plants
(Courtesy of Jeremy K. Greene). Dimensional lines equal 1 mm.