38 Invasive Stink Bugs and Related Species (Pentatomoidea)
2.2.2.1 Key to the Subfamilies of Acanthosomatidae (modified from Kumar 1974a)
1 Abdominal spine absent; posterolateral angles of abdominal segment VII rounded or angu-
late, not spinose (Figure 2.2G); anterolateral pronotal margins thick; Australia, Africa,
South America (Figures 2.15D, E) ................................................................Ditomotarsinae
1’ Abdominal spine usually present but if absent, then either posterolateral angles of last con-
nexival segments spinose (Figure 2.2H) or anterolateral pronotal margins thin ................ 2
2(1) Mesosternal carina usually absent, but if present, it is only a short raised wedge at juncture
of pro- and mesosterna (may extend slightly forward and backward); when both pro- and
mesosternal carinae present then invariably poorly developed (Figure 2.2I) and never con-
tinuous (in such cases abdominal spine well-developed and sometimes reaching anterior end
of prosternal carina); Australia, southern Africa, South America (Figures 2.15C, 2.25A) ....
..............................................................................................................................Blaudusinae
2’ Mesosternal carina usually well-developed and receiving at its posterior end the gener-
ally distally concave abdominal spine, latter closely apposed to sternal carina on left-
hand side (or extending over it, or completely fused with it) (Figures 2.1J,K); worldwide
(Figures 2.15A, B) ...................................................................................Acanthosomatinae2.2.3 Canopidae Amyot and Serville, 1843
The family Canopidae is a small family, both in size (5-7 mm) and number of included taxa with one
genus, Canopus F., and nine species (Table 2.2). Interestingly, twice this many species have been
described, but most were based on nymphal specimens that are now considered to be of unknown
identity (McAtee and Malloch 1928). As with many pentatomoid families, this group was treated
as a subfamily of an inclusive Pentatomidae. Horváth (1919) proposed tribal status for this group
(as Canoparia), and described two new species. The first major monograph of the group (McAtee
and Malloch 1928) treated it as such. It was elevated to family status by McDonald (1979) where it
has remained. The only included genus was described by Fabricius in 1803 to include the species C.
obtectus F., the type specimens of which are all nymphs, thus the type species for Canopus is now
considered to be incertae sedis (McAtee and Malloch 1928). A key to the species was provided by
McAtee and Malloch (1928).
Diagnostic characters (Schuh and Slater 1995, Schwertner and Grazia 2015) for this family
include the following: the bugs have a circular or obovate shape, are strongly convex dorsally,
rather flattened ventrally, and generally are shiny black in color, sometimes with purple or green-
ish reflections (Figure 2.16A). The length of the head anterior to the compound eyes is almost
as long as the width between the compound eyes, and the jugal margins are narrowly reflexed.
The antennae are five-segmented with segment II short, subequal to its diameter. The scutellum
is greatly enlarged, nearly covering the entire abdominal dorsum; only a small fraction of the
hemelytra is exposed. The hemelytra are quite elongate, usually twice the length of the abdomen,
with a line of weakness for folding the wing near the apex of the costa; the wing membrane has at
least five parallel veins. The hind wings have lobate posterior margins; they possess a stridulatory
mechanism composed of a strigil on the posterior anal vein (postcubitus in several earlier papers)
of the hind wing and a plectrum located on abdominal tergum I. The tibiae may be setose, but they
are not distinctly bristled or spined; the tarsi are three-segmented. The abdominal sutures become
obsolete laterad of the spiracles; the abdominal trichobothria are longitudinally placed mesad
of the spiracular line on abdominal sterna III through VII. The nymphs are strongly convex and
sclerotized, with three pairs of dorsal abdominal scent gland openings between terga III-IV, IV-V,
and V-VI; the anterior gland openings are twice the width of the other two; sterna II and III are
divided mesally.
The general habitus, development of the scutellum, and some abdominal and wing characters may sug-
gest a relationship with the Megarididae and Plataspidae; however, other morphological and molecular
evidence are conflicting (Grazia et al. 2008). Schaefer (1981a, 1988) considered the families Canopidae,
Cydnidae, Cyrtocoridae, Lestoniidae, Megarididae, Plataspidae, and Thaumastellidae as primitive