A revision of Scutellera (Hemiptera: Heteroptera: Scutelleridae)
Author
Rédei, Dávid
0000-0003-1550-2110
Department of Entomology, National Chung Hsing University, 250 Kuo Kuang Rd., Taichung 40227, Taiwan. david. redei @ gmail. com; https: // orcid. org / 0000 - 0003 - 1550 - 2110
david.redei@gmail.com
Author
Tsai, Jing-Fu
0000-0003-3076-3976
Department of Biology, National Museum of Natural Science, 1 Kuan-Chian Rd., Taichung 40453, Taiwan. jingfu. tsai @ gmail. com; https: // orcid. org / 0000 - 0003 - 3076 - 3976
jingfu.tsai@gmail.com
text
Zootaxa
2022
2022-01-18
5092
1
1
40
journal article
2502
10.11646/zootaxa.5092.1.1
dde4d25b-55ce-4bae-a486-e6c24ac90528
1175-5326
5869434
3CAF2F90-A654-40B7-BABA-A0035A1A6DE8
Scutellera
Lamarck, 1801
Scutellera
Lamarck, 1801: 293
.
Type
species by monotypy:
Cimex nobilis
(non Linnaeus, 1763):
Fabricius (1775: 697)
, misidentification (=
Tectocoris perplexa
Westwood, 1837
).
Scutellera
: Latreille
([1804a]: 163) (diagnosis, review), Latreille ([1804b]: 176) (diagnosis, review),
Latreille (1807: 112)
(diagnosis, review),
Latreille (1810: 254)
(diagnosis),
Leach (1814: 35)
(diagnosis),
Lamarck (1816: 490)
(redescription),
Latreille (1819: 441)
(diagnosis, review),
Le Peletier & Serville (1828: 409)
(redescription, review), Laporte ([1833]: 67, 70) (in key, redescription),
Burmeister (1835: 395)
(redescription, review),
White (1839: 537)
(
type
species, identity),
Blanchard (1840: 157)
(redescription, review),
Agassiz (1843: 18)
(listed),
Dallas (1851: 4
, 18) (in key, listed),
Dohrn (1859: 2)
(catalogue),
Vollenhoven (1863: 11)
(redescription, fauna of
Dutch East Indies
), Stål ([1865]: 33) (in key),
Mayr (1866: 17
, 22) (in key, listed),
Walker (1867: 15)
(listed),
Stål (1871: 616)
(diagnostic characters),
Stål (1873: 9
, 14) (in key, synopsis),
Atkinson (1887: 161)
(redescription, fauna of
India
),
Lethierry & Severin (1893: 21)
(catalogue),
Kirkaldy (1900: 263)
(listed,
type
species),
Distant (1902: 42
, 50) (in key, redescription, distribution, fauna of
British India
,
Ceylon
and
Burma
),
Schouteden (1904: 15
, 22) (in key, redescription, catalogue),
Kirkaldy (1909: 289
, 303) (catalogue, distribution),
Distant (1918: 116)
(listed),
Hoffmann (1932a: 10)
(listed),
Yang (1934: 238
, 256) (in key, diagnosis, fauna of
China
),
Hoffmann (1935: 181)
(listed),
Tang (1935: 281)
(catalogue,
China
),
Ishihara (1947: 64)
(listed),
Leston (1952: 22)
(listed),
Stichel (1961: 728)
(catalogue, Palaearctic),
Stichel (1962: 208)
(catalogue, Palaearctic),
Fujiyama (1967: 398)
(listed),
Hsiao & Cheng (1977: 55
, 60) (in key, fauna of
China
and
Taiwan)
,
Ahmad
et al.
(1979: 28
, 31, 35) (in key, listed), Ahmad (1980: 124) (distribution in
Pakistan
),
Datta
et al.
(1985: 20)
(listed),
Chen (1987: 125)
(in key),
Chakraborty
et al.
(1994: 473)
(listed),
Ghosh
et al.
(1994: 495
, 496, 498) (listed, in key),
Javahery
et al.
(2000: 491)
(economic importance),
Cassis & Vanags (2006: 286)
(listed),
Göllner-Scheiding (2006: 200)
(catalogue, Palaearctic),
Biswas & Bal (2007: 304)
(in key),
Ghosh (2008: 412
, 417) (in key, diagnosis, species of economic importance in
India
),
Biswas & Bal (2010: 240)
(in key),
Tsai
et al.
(2011: 68
, 151) (in key, redescription, distribution, bionomics, fauna of Taiwan),
Takai &
Ishikawa
(2012: 461)
(redescription, fauna of
Japan
),
Parveen
et al.
(2014: 254)
(morphology),
Parveen & Gaur (2015: 169
, 170, 182) (listed, in key, diagnosis),
Ishikawa
(2016: 492)
(catalogue,
Japan
),
Cai & Cui (2017: 622
, 635) (in key, diagnosis, fauna of Henan).
Calliphara
(non
Germar, 1839
) (misidentification): Amyot & Serville (1843: 30) (redescription),
Kirkaldy (1903: 232)
(listed),
Beier (1937: 2190)
(listed).
Diagnosis.
The specialized metathoracic scent gland ostiole (provided with a long and strongly widened, almost semicircular peritreme, evaporatorium strongly reduced) (
Fig. 19
: arrow; see also
Fig. 12
) is diagnostic for
Scutellera
. Other characters useful for recognizing this genus are the elongate oval body (
Figs. 1–3, 5, 6, 8, 9
,
11–13, 15, 16
,
18–23
) covered by rather long, dense, erect to semierect pilosity, the presence of a wide and deep transverse furrow in the middle of the pronotum, and the long median furrow on the abdominal venter (extending to about the base of ventrite VII); these character states are also found in the closely related
Brachyaulax
Stål, 1871
, although the median furrow is only distinct on ventrites II–III in the latter.
Redescription.
A redescription of the genus by
Tsai
et al.
(2011)
was based on
S. nepalensis
and
S. perplexa
. The transfer of
S. spilogastra
into
Scutellera
necessitates a revised redescription, as provided below.
Body
medium to large (about
15–25 mm
), elongate oval, moderately convex dorsally and ventrally; dorsal outline of body distinctly excised between base of scutellum and base of pronotum in lateral view (
Figs. 2
,
12
).
Body surface and vestiture.
Dorsum with strong metallic lustre, sometimes with dull to subshining black spots; venter dull with large metallic spots; body and legs covered by dense, erect to semierect pubescence, smooth, with very small and fine, densely and evenly distributed, uniform punctures, head, pronotal calli, and base of scutellum usually more finely or indistinctly punctured, calli bordered by large, coarse punctures anteriorly and posteriorly; scape and basipedicellite with very few, scattered hairs, distipedicellite and flagellum with short and dense pilosity.
Head
stout, 1.1–1.15 times as wide as its median length, 1.3–1.4 times (
♂
,
♀
) as wide as interocular distance, convex, moderately declivous; lateral margin deeply emarginate anteriad to eyes, obtuse; clypeus slightly surpassing mandibular plates; mandibular plates rounded anteriorly; buccula unarmed; eyes relatively small, moderately protruding laterally; ocelli small, situated slightly posteriad to posterior margin of eye, relatively far from eye.
Antenna
five-segmented, apex of scape far remote from apex of head, basipedicellite much shorter than distipedicellite; scape and pedicellite cylindrical, basi- and distiflagellum flattened.
Labium
reaching from about base of abdomen to posterior margin of ventrite IV.
Pronotum.
Anterior margin with impressed collar; calli distinct, fused medially, demarcated by a wide and deep transverse furrow posteriorly, cicatrices distinct; lateral margin nearly straight or slightly concave, narrowly carinate; humeral angle rounded; posterior margin nearly straight; posterolateral angle angulate.
Scutellum
wide, usually leaving only extreme margin of abdomen, base of exocorium and extreme base of endocorium exposed; with an indistinct, obscurely demarcated basal tumescence; rather strongly tapering towards apex posteriad of middle; apically broadly truncate. Membrane not or only narrowly exposed beyond apex of scutellum at rest.
Thoracic pleura and sterna
. Anterior explanate part of proepisternum weakly projecting anteriad; pterothoracic sternum with rather deep median furrow; metathoracic scent gland ostiole provided with a long and strongly widened, almost semicircular peritreme occupying almost all the metepisternum, its anterior margin nearly straight, posterior margin widely convex, with a shallow furrow running along posterior margin (
Fig.19
: arrow; see also
Fig. 12
); evaporatorium reduced, present only as narrow bands anteriad and posteriad of peritreme, not extending to mesopleuron (see also
Tsai
et al.
2011: 16
, fig. 15 and
Parveen et al. 2014: 240
, fig. 2G and 254, fig. 19).
Legs
short; femora thick, unarmed; dorsal surface of tibiae with a wide longitudinal furrow.
Pregenital abdomen
with a median longitudinal furrow extending to about base of ventrite VII; lateral margin obtuse; posterolateral angles of ventrites II–VI not produced, those of segment VII produced into a pair of conical, apically pointed processes; opening of dorsal abdominal scent glands of segment III far remote from lateral margin of abdominal tergites, situated about halfway between opening of those of segment IV and lateral margin of tergite IV.
External male genitalia.
Genital capsule (
Figs. 30, 34, 38
) narrowed posteriad, with a pair of minute submedian denticles on its posterior margin; dorsal setal patches continuous medially, band-like, narrowly bordering dorsal sinus; ventral setal patches extensive, situated on area of ventral infolding surrounding cuplike sclerite. Paramere (
Figs. 31–33, 35–37, 39–41
) fully sclerotized, lacking desclerotized neck, stem elongate and columnar, crown short and hooked, a lateral, apically blunt flange provided with setae present.
Phallus
(
Figs. 42–52
) symmetrical; phallotheca with a pair of callose thickenings dorsolaterally; conjunctiva with two pairs of processes (second and third pairs of the groundplan, cf.
Tsai
et al.
2011
), second pair (cp-II) subdivided into cp-II
1
(lobe-like, of lateral position, at least partly sclerotized) and cp-II
2
(of mesal position, enclosed by cp-II
1
, greatly membranous, with a sharp, sclerotized process apically), third pair (cp-III) heavily sclerotized, of various length and shape; aedeagus
s. str.
short, S-shaped, apex truncate; endophallic reservoir elongate oval, with double chamber, endophallic duct of two lumina system; aedeagal conducting tube very short, stout, constricted at middle, closely adhered to ventral angulate concavity of aedeagus
s. str
.
External female genitalia.
Ovipositor plates posterior, almost vertical (
Figs. 53–55, 57–59, 61–63
); laterotergites IX obliquely directed, fused valvifers IX partly exposed, with an obtuse median longitudinal keel. Gynatrium with a pair of long anterolateral pouches; ring sclerite long, far surpassing apex of fecundation canal, approaching apex of anterolateral pouch (frequently thin, inconspicuous,difficult to trace); a pair of small, transverse sclerites, occasionally fused along midline, present posteriad of spermathecal opening; fecundation canal forming a long and narrow, rodlike sclerite broadened or bifurcate distally, provided with a deep median furrow (
Figs. 65, 67, 69
). Spermatheca with distal duct somewhat shorter and narrower than proximal duct; dilation with wall regularly, obliquely fluted externally, thick, sclerotized, inner surface provided with several thin, lamellate projections projecting into the inner lumen, invaginations of proximal and distal spermathecal ducts simple, apical receptacle (
Figs. 66, 68, 70
) strongly elongate, with a globose apex.
Distribution and diversity.
The genus is endemic to Indomalaya, and it occurs all over the region, also entering the Wallacea marginally (
Figs. 71, 72
). It contains three described species.
Phylogenetic considerations.
Scutellera
and
Brachyaulax
share a number of skeletal characters mentioned in the diagnosis. The genitalia of both sexes are also highly similar, including a similar articulatory apparatus (particulary the sclerotized part of the erection pump), the phallotheca being provided with a pair of callose thickenings dorsolaterally, the similar shape of the conjunctival processes (both cp-II and cp-III) and the aedeagal complex in the male, and the presence of a median longitudinal carina on the fused valvifers IX, the elongate fecundation canal with a pair of apical projections, and the similar spermathecal dilation in the female (cf.
Tsai
et al.
2011
). These morphological similarities likely indicate a close phylogenetic relationship, probably a sister relationship, between these two genera.
Scutellera
(together with
Brachyaulax
) is a highly specialized genus of Scutellerini, exhibiting several putative apomorphies within the subfamily. Due to its specialized morphology the polarity of several characters within the genus is difficult to determine. The laterally emarginate genital capsules (
Figs. 24, 25
,
30
vs. 28, 29, 38), similar shape of the conjunctival processes (particularly the lobe-like, externally partly sclerotized cp-II
1
) (
Figs. 42, 43
vs. 46, 47), enlarged laterotergites VIII (
Figs. 53–55
vs. 61–63), the similar shape of fused valvifers IX (
Figs. 56
vs. 64), and the presence of a single transverse sclerite of the gynatrium posteriorad the opening of of spermathecal opening (
Figs. 65
vs. 69) are apparently shared characters between
S. nepalensis
and
S. spilogastra
, but it is difficult to establish whether they are synapomorphies or symplesiomorphies. The problem cannot be solved without examining a larger sample of Scutellerini with cladistic methods.
Remarks.
Several authors in the early 19th century (
Latreille [1804a]
, [1804b], 1807, 1810, 1819,
Leach 1814
,
Le Peletier & Serville 1828
,
Laporte [1833]
,
Burmeister 1835
,
Blanchard 1840
, etc.) used this generic name in a broad sense, in a way highly different from the current usage (sometimes also including various non-scutellerid pentatomoids with enlarged scutellum).
Scutellera
of Westwood (1837: 3),
Germar (1839: 132)
and Amyot & Serville (1843: 27) did not contain the
type
species (whilst all of them listed it under different genera), whilst the definitions of
Scutellera
provided by
Hahn (1833: 172)
and
Schiødte (1843: 295)
conflict with the
type
species and evidently correspond with
Graphosoma
Laporte, [1833] (Pentatomidae)
and
Tectocoris
Hahn, 1834
, respectively; accordingly they must be considered as misidentifications of the genus.
Key to the species of
Scutellera
1
(4) Body elongate, 2.3–2.4 times as long as its greatest width, scutellum 1.7–1.8 times as long as its greatest width; pronotum and thoracic pleura with extensive orange or red markings, peritreme red; femora red, with metallic blue-green annulus apically (
Figs. 1–3
,
11–13, 15, 16
,
18–23
)........................................................................
2
2
(3) Dorsum with extensive, confluent markings, spots of scutellum invariably united into broad transverse fasciae (
Figs. 1, 2
,
11, 12, 15
); lateral margin of genital capsule deeply emarginate (
Figs. 24, 25
,
30
: arrow) (
♂
); lateral portions of laterotergites VIII forming a pair of strongly protruding, rounded, lobe-like projections (
Figs. 53–55
: arrow), laterotergites IX relatively large, elongate, broadly separated in rest (
Figs. 53, 54
: lt
9
) (
♀
) (Sub-Himalayan belt, South
China
, Indo-China,
Taiwan
, Ryūkyū Archipelago, Malay Archipelago)........................................
Scutellera nepalensis
(Westwood, 1837)
3
(2) Dorsum with reduced markings composed at most of a narrow median vitta and isolated paired submedian spots which are never confluent (
Figs. 18, 20
), but frequently without any markings (
Fig. 22
); lateral margin of genital capsule not emarginate (
Figs. 26, 27
,
34
) (
♂
); lateral portions of laterotergites VIII flat, not protruding posteriad, laterotergites IX smaller and shorter, more rounded, closely approaching each other or adjacent in rest (
Figs. 57–59
) (
♀
) (
Indian Subcontinent, Indo-China
, South
China
)..............................................................
Scutellera perplexa
(Westwood, 1837)
4
(1) Body distinctly broader, about 2.1–2.15 times as long as its greatest width, scutellum 1.35–1.45 times as long as its greatest width; pronotum and thoracic pleura without orange or red markings, peritreme black; femora nearly uniformly metallic bluegreen (
Figs. 5, 6, 8, 9
) (southern
India
,
Sri Lanka
).............................
Scutellera spilogastra
(
Walker, 1867
)