86 Invasive Stink Bugs and Related Species (Pentatomoidea)
that Wall (2007) recognized a separate clade within the Halyini, called the Solomonius group, character-
ized by extremely reduced parameres in the male genitalia that are fused with the proctiger complex. His
Solomonius group contains seven genera, namely Anchises Stål, Auxentius, Babylas, Brizica, Elemana
Distant, Epitoxicoris, and Solomonius Wa l l.
There are still several genera placed in the Halyini that seem to not belong. For example, Eurus Dallas
has a different head structure and the mesosternum is sulcate; Goilalaka, in general appearance, seems
quite similar to the genus Aednus (now in Myrocheini but probably belongs in the Caystrini or a related
t r ibe); Mimikana, which actually is reminiscent of some members of the Ochlerini; and Tinganina
Bergroth, which exhibits a different head structure (i.e, the bucculae are distally toothed), and many
specimens exhibit brachyptery (not seen in other halyine genera). Polycarmes Stål has both the mesoster-
num and the metasternum sharply carinate medially; this condition of the metasternum is relatively rare.
The correct placement of these genera will probably not be known until a thorough phylogenetic study is
completed. The genus Surenus will be transferred to the Caystrini (Salini Shivaprakash and Petr Kment,
unpublished data). On the other hand, two tribes defined mostly by reductions, Memmiini (3-segmented
tarsi and 4-segmented antennae) and Nealeriini (2-segmented tarsi and 4-segmented antennae), may be
synonyms of the Halyini (Linnavuori 1982, Kment 2013).
There may even be some question on whether the only New World representatives, Brochymena
(Figure 2.21K) and Parabrochymena, are true halyines. Again, this is a question that will only be
answered via a new phylogenetic study. Species of these two genera are quite similar in general appear-
ance; in fact, the validity of Parabrochymena has been questioned. A relatively recent study (Ahmad and
McPherson 1998) confirmed that there are differences between these two genera; whether these differ-
ences are great enough to warrant separating this group into two genera may require further study. The
biology of a species of each genus also has been studied (Cuda and McPherson 1976).
Several halyine genera have been reviewed in recent years: Apodiphus Spinola (Ghauri 1977a),
Auxentius (Wall 2007), Brizica (Wall 2007), Brochymena (Ruckes 1947, Larivière 1992), Cahara Ghauri
(Ghauri 1978, Fan and Liu 2013), Carenoplistus (Memon and Ahmad 1998), Ectenus (Uichanco 1949),
Epitoxicoris (Wall 2007), Faizuda Ghauri (Ghauri 1988b), Goilalaka (Ghauri 1972), Halys F. (G h au r i
1988a), Jugalpada Ghauri (Ghauri 1975a), Parabrochymena (Larivière 1994), Paranevisanus Distant
(Ghauri 1975b), Platycoris (McDonald 1995), Poecilometis (Gross 1972), Sarju Ghauri (Ghauri 1977b,
Memon and Ahmad 2009), Solomonius Wall (Wall 2007), Tachengia China (Ahmad 2004), Theseus Stål
(Baehr 1989, 1991), Tipulparra Ghauri (Ghauri 1980), and Zaplutus Bergroth (Cachan 1952).
It appears that most halyine species are arboreal, residing on various trees; their dark mottled color-
ation allows them to blend in well with the bark of trees.
2.2.10.7.24 Hoplistoderini Atkinson, 1888
This group was first recognized by Stål (1876), but he did not formally name it. He included four genera
in his “Hoplistodera, Alcimus et affinia”: Alcimus Dallas (= Alcimocoris Bergroth), Ta urodes Dallas,
Hoplistodera Westwood, and Stachyomia Stål. Atkinson (1888) was the first to formally name this tribe,
and he originally included three genera in his Hoplistoderaria: Alcimus, Hoplistodera, and Bolaca.
Distant (1902) transferred Bolaca to the Amyntorini, where we currently treat it, and added two more
genera, Axiagastus (now in the Axiagastini) and Paracritheus Bergroth (still considered to belong in the
Hoplistoderini). Bergroth (1918) described the genus Glottaspis, placing it near the genus Alcimocoris.
Members of this tribe tend to be small to medium in size; they are somewhat robust in form with a
tendency for the humeral angles to be produced, the scutellum to be enlarged (spatulate) (Figure 2.30D),
and the head and anterior disk of pronotum to be quite declivent. Otherwise, however, there is some vari-
ability in structure. For example, Hoplistodera and Stachyomia both have the mesosternum distinctly
carinate medially, whereas Alcimocoris has a sulcate mesosternum. The ostiolar rugae are usually elon-
gate, reaching beyond the middle of the metapleura. The abdominal venter is unarmed.
This is not a large group with most genera and species known from the Indian-China region south-
eastward into Southeast Asia with Glottaspis being endemic to Madagascar. There are seven genera and
35 species (Table 2.3). Distant (1902) indicated a possible relationship with the Eysarcorini as members
of both tribes usually have the scutellum enlarged, and they tend to have a somewhat shortened, robust