Invasive Stink Bugs and Related Species (Pentatomoidea)

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Higher Systematics of the Pentatomoidea 57


In a study of the aedeagus of the Asopinae, Gapon and Konstantinov (2006) found three more or
less distinct patterns; however, one genus (Euthyrhynchus Dallas) was difficult to place into any of the
categories. As only 18 of the 63 asopine genera were studied, and no studied genus included more than
one species (which might have provided information on how plastic or consistent the characteristics are),
the results of this work should be tested on a larger sample. The three groups outlined by Gapon and
Konstantinov did not correspond to the groups possessing or lacking male abdominal glands. This lack
of congruent pattern might suggest that either the male genital characters, or the abdominal glands, or
perhaps both are subject of convergent/homoplastic evolution. Gapon and Konstantinov wisely eschewed
proposing tribal designations for their schemes, a decision we support.
Only two fossil species have been described in the Asopinae, one of which has been transferred into
the Pentatominae. The species still treated as an asopine is Asopus puncticollis Piton (1940). The other
species, Arma contusa Förster (1891), was later placed as a synonym of Eysarcoris mammillata Förster
(Théobald 1937), which is a member of the Pentatominae: Eysarcorini.


2.2.10.4 Cyrtocorinae Distant, 1880


The Cyrtocorinae is a small subfamily containing four genera and eleven species, all restricted to
the New World tropics (Tables 2.2, 2.3). They have bounced back and forth in being considered
a subfamily within the Pentatomidae or being a separate family. For example, historically, Dallas
(1851) and Walker (1867a) (using the synonymic preoccupied name Oxynotidae) treated this group
as a family, Distant (1880) as a subfamily, Lethierry and Severin (1893) as a family, Kirkaldy
(1909) as a subfamily, and so on. More recently, Schuh and Slater (1995) treated it as a subfamily,
but Packauskas and Schaefer (1998), in their revision of the group, treated it as a family. The cla-
distic study of Grazia et al. (2008) supported the treatment of this group as a subfamily within the
Pentatomidae. We also treat it as a subfamily, supported heavily by its members having a dilation
and a sclerotized rod in the female spermathecal duct. Amyot and Serville (1843) first recognized
this taxon as a family level group under the name Oxynotides; this name, however, was based on a
preoccupied generic name, Oxynotus Laporte. Family names based on preoccupied generic names
are not allowed, so White (1842) proposed Cyrtocoris as a replacement generic name, but it was
Distant (1880) who first used Cyrtocorinae as a family-level name.
Members of this family are small to medium in size (6-10 mm), somewhat squarish in shape (Figure
2.27C), sometimes with long spine-like projections in various directions. They are usually dark grey to
black in color, but often appear somewhat lighter because of the presence of many small brown-tan or
white scale-like setae (Rolston and McDonald 1979, Packauskas and Schaefer 1998). Their dorsal sur-
face is quite roughened, irregular, and almost granulate (Figures 2.17G, 2.27C). They are characterized
by the flattened expansions of the juga; the form of the scutellum, which usually reaches the apex of the
abdomen; and the presence of a rather robust dorsal thorn-like protuberance on the scutellum (Figure
2 .17G). The antennae are four-segmented. The tarsi are two-segmented.
Brailovsky et al. (1988) described life history traits of two species, Cyrtocoris egeris Packauskas and
Schaefer and C. trigonus (Germar), which are summarized here. The eggs are deposited in grooves in
the bark of hosts in masses of variable number (usually more than ten eggs). The nymphs are gregarious
and remain on the same host during their entire development, which can last about 45 days. There is one
generation per year, and the insects hibernate as adults. These species are exclusively phytophagous,
and feeding sites mainly include the branches of the hosts. Host plant associations include species of
Araceae, Euphorbiaceae, Fabaceae, Malvaceae, and Piperaceae (Brailovsky et al. 1988, Schaefer et al.
2005). The eggs and first-fifth nymphal instars of C. egeris have been recently studied by Bianchi et al.
(2 011).


2.2.10.5 Discocephalinae Fieber, 1860


The Discocephalinae presently contains 81 genera and 325 species, all endemic to the New World
tropics (Tables 2.2, 2.3). Fieber (1860) proposed Discocephalidae to include Discocephala Laporte,
Dryptocephala Laporte, and Platycarenus Fieber. The taxon was treated as a subfamily by Stål (1868),

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