New genera, species and subspecies of tessaratomine true bugs (Heteroptera: Tessaratomidae, Tessaratominae)
Author
Magnien, Philippe
text
Zootaxa
2023
2023-11-24
5375
4
533
549
https://www.mapress.com/zt/article/download/zootaxa.5375.4.5/52344
journal article
10.11646/zootaxa.5375.4.5
1175-5326
10202772
648DD26D-F271-4BD2-ADFB-0C5C31191FF1
Oukhypencha
gen. nov.
Type
species.
O. clemenceae
sp. nov.
, by present designation.
Diagnosis.
Medium sized
Tessaratomina
(
19–26 mm
), characterized by the following set of characters: head very small, with eyes and ocellae relatively large (ocular index 1.1–1.3, ocellar index 1.1–1.9), antennae long, little more than half (0.50–0.69) of habitus length; connexivum bicolourous; prosternal process lanceolate, rounded, sides not flattened, reaching or surpassing fore coxae.
Description.
Body of the common pentatomoid shape (
Figs. 1–7
), general hue bronze brownish above, of a lighter brownish ventrally; apex of fourth antennomere, apex of scutellum and forepart of each connexivum segment yellowish.
Head. Triangular, mandibular plates surpassing tylus, entirely punctate, save for a small area around ocellae; antennae 4-segmented, long; eyes and ocellae relatively large, ocular index 1.1–1.6.
Thorax. Pronotum sexangular, anterior, posterior and anterolateral margins nearly straight, posterolateral margins slightly bisinuous; callosities conspicuous, slightly marked. Scutellum triangular, longer than wide, its apex lanceolate. Metasternum with an elevated plate between coxae, bearing a rounded lanceolate process reaching or surpassing fore coxae, curved upwards at apex; evaporatoria small (
Fig. 23
), in accordance with the description given for the tribe in Kment &Vilimova (2010).
Abdomen. Connexivum and urosternite margins straight; spiracles closer to margin than to middle of the sternites, trichobothria closer to middle, aft of transverse furrow.
Male genitalia (Figs. 11–13, 15–18). Pygophore of various shapes. Parameres having shape of a recurved blade, rounded at apophysis, sensorial lobe conspicuous, marked by a brush of setae about as long as parameral width; phallus bearing three or four processus, two of them strongly sclerotized, lateroventral process strong, scythe blade-shaped.
Female genitalia (
Figs. 19–22
). Genital plates of general shape found in
Tessaratomini
. Spermatheca of common
type
in
Tessaratomini
; apical receptacle (distal bulb) spherical with a basal “neck”, intermediate part (pump apparatus) with two well-developed flanges; spermathecal duct bipartite, anterior duct slender, posterior duct much wider, its anterior part slightly ovoid and longitudinally striated, rear part somewhat longer.
Etymology
. The name
Hypencha
was crafted by its authors from the Greek ύπό, under and ἕγχος, sword. Ι added the prefix
Ouk
, from the Greek οὑκ, not, to imply it was not belonging in
Hypencha
.
Distribution
. Peninsular
Thailand
,
Malaysia
,
Indonesia
(
Java
,
Sumatra
,
Kalimantan
).
Discussion
. During this study, it became very apparent that previously identified material of
H. ophthalmica
was in fact a composite of at least four different species. The difficulties were a result of problems in the proper identification of the male of Stål’s species, and in the true generic placement of these taxa. Regarding the first problem, unfortunately, no specimens from Peninsular
Thailand
or
Malaysia
were available for study, so the decision was made to select the taxon with the most similar female genitalia as representing
H. ophthalmica
. It is one of the species from Sumatra, which is also among the closest to the
type
locality in
Thailand
.
Regarding the generic placement, it was quickly determined that for the involved taxa for which male specimens were available for study, none of them could fit in
Hypencha
. In fact, the variation in the male genitalia observed could have justified the creation of several different genera. Despite this variability, I have chosen to take a conservative approach and place all of these taxa in a single new genus,
Oukhypencha
gen. nov.
Its habitus is similar to that of other tessaratomine genera, the closest being
Hypencha
, the genus in which Stål originally placed
H. ophthalmica
. In general, the male genitalia are indeed very good characters to use in delineating tessaratomine genera. That is, the male genitalia are usually very similar among species within each genus, but they usually vary distinctly between genera (except for a couple, e.g.,
Embolosterna
Stål
and
Tessaratoma
Berthold
1
), to the point that it is usually fairly easy to identify a genus from the examination of the male genitalia alone (see
Kumar & Ghauri, 1970
). The phallus of
Hypencha
, according to
Kumar and Ghauri (1970)
, can be characterized by:
“
Hypencha
,
Mucanum
,
Embolosterna
and
Tessaratoma
, all have three pairs of conjunctival processes.”
Hypencha
is distinct in having two pairs of ventral conjunctival processes.
They add that the anteroventral one is membranous, and that the paramere is elongate, apically curved. Those descriptions do not match the organisation of the genitalia in the new genus.
The conjunctiva of
Oukhypencha
bears three or four pairs of processes, but even in those species with three pairs, their disposition is not homologous with those of
Hypencha
.
Hypencha
(
Fig. 15
) lacks the ventral sclerotized and membranous processes, while
Oukhypencha
(
Figs. 16–18
) species lack the proximoventral process. The dorsal process is sclerotized in
Hypencha
, while it is membranous in the new genus, except for
O. florenceae
which has two dorsal processes, the distal process is membranous, while the proximal process is sclerotized. Furthermore, the parameres (
Figs. 16–18
) are not digitiform as those found in species of
Hypencha
(
Fig. 15
), and they possess a conspicuous sensorial lobe with a dense brush of setae, which is absent in all examined specimens of
Hypencha
. Some differences, probably of less generic significance, listed in the diagnosis, can be found in the habitus. The antennae are relatively long for a tessaratomine, from about 50 to 70 % of the habitus length, whereas in
Hypencha
specimens, the antennae are about one-third of the habitus length, except for
H. aeroplana
in which it reaches less than half the habitus length. The ocellae are very large. The free part of the sternal process is rounded, not flattened, as is the case in
Hypencha
.
The connexivum is bicolorous in
Oukhypencha
, contrasting with unicolorous in
Hypencha
species.
The apex of the scutellum is large and concolorous in
Hypencha
, while it is thin and more or less yellowish in
Oukhypencha
. The size of the eyes and ocellae is larger for
Oukhypencha
(ocular index 1.1–1.6, ocellar index 1.1–3.5) than for
Hypencha
(ocular index 1.3–1.6, ocellar index 2.0–5.5).
1 The synonymy between these two taxa should be examined on this basis; no character, except for the shape and colouration of the post-frenal part of the scutellum, has been found that can reliably separate the two genera. The conclusion of
Kumar and Ghauri (1970)
on this point is not sustainable, as their key would place
E
.
vacca
Martin, 1902
, within the genus
Tessaratoma
.
The choice to designate
O. clemenceae
n. sp.
as the
type
species for this new genus was made on the basis that both male and female specimens where readily available in good numbers, which is not the case with the previously described
O. ophthalmica
for which male specimens are still unknown for the nominal subspecies.