Cimex gastricus, (Thunberg, 1822)

Tsai, Jing-Fu & Rédei, Dávid, 2009, The identity of shield bugs described by Francis Walker from Taiwan (Hemiptera: Heteroptera: Pentatomidae), Zootaxa 2152, pp. 43-54 : 49-53

Laprius gastricus ( Thunberg, 1822)

Figs. 3 , 20–40.

Cimex gastricus Thunberg, 1822: 1 . Syntype (s): „Capensis” [= South Africa] (in error?); UZIU.

= Sciocoris lugubris Walker, 1868: 538 . Syntype (s): „ Formosa ” [= Taiwan]; MVMA. New synonymy.

Main references for Laprius gastricus . Stål 1855: 182; 1856: 56 (redescription); Rider 2006: 323 (catalogue).

References for Sciocoris lugubris . Lethierry & Severin 1893: 108 (as of doubtful generic placement); Distant 1899: 445 (list, type depository); Kirkaldy 1909: 210 (as of unknown identity); Esaki 1926: 147 (as of doubtful generic placement); Hoffmann 1935: 98 (catalogue, as of doubtful generic placement); Hsiao & Zheng 1977: 104 (note, as of doubtful identity); Rider et al. 2002: 145 (as of doubtful identity); Rider 2006: 356 (as possibly belonging to Caystrini).

Type material examined. LECTOTYPE (3), by present designation: „ TYPE ” [red square, printed]; „ Sciocoris \ lugubris \ Formosa ” [Walker’s handwriting]; „ HOLOTYPE \ T-20189 \ Sciocoris \ lugubris \ Walker” [red square, printed + handwritten]; „ LECTOTYPUS \ Sciocoris lugubris \ Walker, 1868 \ des. Tsai JF & Rédei D, 2009”; MVMA. Pinned; right antennal segments IIa–IV, tarsus of left fore leg, tibiae, and tarsi of right fore, left mid, and left hind legs, tarsal segments II–III of right mid leg, femur, tibia, and tarsus of right hind leg missing ( Fig. 3 ). Genitalia dissected and figured ( Figs. 26–39 ), preserved in microvial with glycerine, pinned with the specimen.

Other specimen examined. TAIWAN: „Takao” [= Kaohsiung], 1907, leg. H. Sauter (1 ♀; HNHM) (female genitalia illustrated). — “Ostindien” [= East Indies] (1 ♀ identified by Stål, 1 specimen lacking abdomen identified by Stål, 1 3, 1 ♀; NHMW).

Redescription. Colour and integument. Dorsum brown, dull, bare, with dense, dark brown punctures; head uniformly brown with impunctate spots posteromedian to eye; antennal segments I, IIa, and IIb reddish yellow, segments III and IV black; labium yellowish brown, apical half of segment IV black; pronotum brown, explanate lateral margins slightly lighter; scutellum brown, basolateral callosities yellowish, confluent dark brown punctures appearing as black spots mediad to basolateral callosities and at basal margin of scutellum, apex of scutellum light; fore wings brown, membrane smoky brown; legs yellowish brown, with brown punctures on femora and tibiae; abdominal connexival segments black, laterally narrowly margined with yellow, middle of each connexival segments with a yellow rounded spot; venter of head, thorax, and abdominal sternite II yellow, with rough, dark brown punctures, in some places of thoracic pleuron confluent and forming larger black spots; venter of remaining segments of pregenital abdomen yellow, with a pair of wide, blackish sublateral stripes extending from base of sternite III to middle of sternite VI, interrupted on sternite V; basal fifth of extreme lateral margin of abdominal sternites III–VII black; abdominal sternite VII with a pair of small submedian spots at its posterior margin; abdominal sternites with fine, light brown punctures mediad to sublateral blackish stripes, and with fine, colourless punctures laterad to these stripes; abdominal spiracles margined with black.

Structure. Macropterous male and female, body wide oval as characteristic for genus ( Fig. 3 ) about 1.7 times as long as greatest width of abdomen. Head (Figs. 20, 21) elongate, slightly declivent in basal twothirds, more strongly declivous from middle of clypeus; median length about as long as width across eyes; width across eyes about 1.5 (3) / 1.4 (♀) times as wide as interocular distance; distance between ocelli nearly two times as long as distance between eye and ocellus; mandibulary plate distinctly surpassing apex of clypeus, apically rounded, lateral margin explanate and widely elevated in basal half, lateral outline S-shaped in dorsal view; antenniferous tubercles extending into an elongate, pointed, spine-like teeth directed anteriad, quite visible in dorsal view; buccula forming a blunt angle anteriorly. Antenna. Segment I extending approximately to apical third of preocular part of head; segment IIa about 1.85 times as long as segment IIb. Labium approaching posterior margin of abdominal sternite III (Fig. 20). Pronotum (Figs. 20, 22). Lateral margin explanate, nearly straight around middle, rounded anterolaterad to humeral tumescence; posterior margin almost straight at base of scutellum; anterolateral angle forming a blunt, short teeth projecting anterolaterad, extending about middle of eye in dorsal view; disc with 2 pairs of small whitish callose tubercles immediately posteriad to cicatrices, external pair larger than internal. Scutellum of medium size, frenal portion occupying approximately basal three-fifths, postfrenal portion occupying approximately apical two-fifths of total length, postfrenal portion subtriangular, subpointed; basolateral angles with a pair of large yellowish callosities. Fore wing not reaching apex of abdomen, thus leaving connexival segments free, apex of corium far surpassing apex of scutellum; base of subcostal vein with two small, elongate oval callose spots. Thoracic pleuron and sternum. Peritreme of scent gland ostiole small, ear-like (Figs. 23–25); puncturation on metapleurite laterad and posteriad of scent gland ostiole forming thick wrinkles; posterior flange of metapleurite smooth hetween punctures (Fig. 23); pro-, meso-, and metathoracic sternum forming a single wide and shallow longitudinal furrow. Legs. Fore and mid femora with two series of distinct teeth each bearing a single, thick, spine-like seta apically, apicalmost tooth of anteroventral series of fore femur distinctly larger than remaining teeth; tibiae with several thick, almost spine-like setae; tarsi with fine hairs. Abdomen. Sternite II similar in sculpture to metathoracic pleuron; sternite III with a pair of submedian carinae surrounding apex of labial segment IV; sternites III and IV with a pair of submedian, transverse, impunctate, subshining stripes. Male genitalia. Pygophore ( Figs. 26–28 ) subquadrate in ventral view, with oblique depression below ventral rim, with evenly distributed, deep punctures; ventral margin with pair of very short, rounded submedial projections; genital opening large, with pair of small ventrolateral excisions for reception of parameres, with a rigid, scoop-like median sclerite (subgenital plate) ventrally; lateral margin of genital opening with pair of projections anterolaterally; ventral surface, ventral rim, and infolding of lateral rim with scattered hairs. Parameres ( Figs. 29–31 ) symmetrical; with large, wide flange around middle, bearing long setae; apical part narrow, strongly curved, finger-like, its ventral surface densely covered with minute tubercles. Phallus ( Figs. 32–39 ). Phallotheca short and stout, barrel-like, constricted subapically, constriction continued in a septum internally, having a circular perforation ( Figs. 34, 36 ); conjunctiva with three sets of processes (cp1–cp3) as follows: cp1: a pair of sclerotized processes at dorsolateral margin of conjunctiva; cp2: a pair of heavily sclerotized, apically widely bifurcate processes neighbouring the vesica; cp3: a pair of lateral, partly sclerotized processes; ejaculatory reservoir large, occupying approximately three-fourth of phallic cavity, distal part strongly sclerotized and pigmented exteriorly; vesica stout, curved, apically truncated, heavily sclerotized. Female genitalia ( Fig. 40 ). Posterior margin of abdominal sternite VII with a deep, rounded median excision, VIIIth gonocoxites situated within excision of sternite VII, their medial margin straight, posterior margin deeply concave, with strong setae along medial margin; IXth paratergite broadly triangular, with several strong setae along its medial and lateral margins, greatly thickened along median margin, widely rounded apically, its apex extending to posterior margin of tergite VIII.

Measurements (in mm; male syntype of lugubris / female in HNHM). Body length from apex of clypeus to apex of abdomen 10.1 / 9.3; length of head along meson to apex of clypeus 2.21 / 2.32, width across eyes 2.56 / 2.32, interocular distance 1.68 / 1.66, interocellar distance 0.96 / 0.86, distance between eye and ocellus 0.37 / 0.44, lengths of antennal segments as (I) 0.54 / 0.52: (IIa) 0.98 / 0.98: (IIb) 0.53 /?: (III) 0.95 /?: (IV) 1.32 /?; length of pronotum along meson 1.97 / 1.98, greatest width 5.36 / 5.03, length of scutellum 3.36 / 3.40, basal width 3.23 / 3.15, greatest width of abdomen 5.52 / 5.35.

Discussion. Laprius gastricus is the type species of the genus Laprius ( Stål 1861: 200). The species was described from South Africa (“Capensis”), but apparently in error. Later Stål (1855, 1856, 1876) recorded it from “ India orientalis” [= East Indies] and Japan, and gave a brief redescription.

Four ancient specimens from “ India orientalis” identified by Stål as L. gastricus , deposited in NHMW, were examined. The redescriptions by Stål (1855, 1856) were probably based at least partly on these specimens.

According to the examined male syntype of Sciocoris lugubris , hereby designated by us as a lectotype, Walker’s original description is inaccurate in some respects; nevertheless, several details, especially the detailed description of the venation of the membrane (otherwise without taxonomic value), leave no doubt that the specimen deposited at MVMA is the same specimen which was studied by Walker. The lectotype is recognized by us as conspecific with the four specimens of L. gastricus identified by Stål; therefore S. lugubris is hereby placed as a junior synonym of L. gastricus .

The genus Laprius is in need of revision. Moreover, we are aware of some confusion about the included species in the literature before us. In order to facilitate future work on the genus and the recognition of its type species, we provide a detailed redescription and several illustrations of L. gastricus (partly based on the lectotype of Sciocoris lugubris ).

Ahmad and Kamaluddin (1986) described a new genus of Myrocheini, Dollingiana, from India. Unfortunately, they presented no differential diagnosis for their new genus, and only gave a little information on how to differentiate it from other genera of the tribe. According to the descriptions and figures of Dollingiana spp. presented by Ahmad and Kamaluddin (1986), it was concluded that the differences between Laprius and Dollingiana are obscure. Both of the characters listed by Ahmad and Kamaluddin as suitable for differentiating Dollingiana from “many members of Laprius ” do occur in L. gastricus , the type species of Laprius. Consequently, Dollingiana is probably a junior synonym of Laprius.

Figures

FIGURES 1 – 3. Holotypes and labels of 1, Eysarcoris latus Walker, 2, E. pustulatus Walker and 3, Sciocoris lugubris Walker. Scales in mm.

FIGURES 26 – 40. Laprius gastricus (Thunberg), male and female genitalia. 26 – 28, pygophore, caudodorsal, ventral, and lateral views, respectively; 29 – 31, right paramere, three different views; 32 – 33, articulatory apparatus, dorsal and lateral views, respectively; 34 – 36, lateral phallotheca, dorsal, lateral, and posteroventral views, respectively; 37 – 39, conjunctiva and its appendages, dorsal, lateral, and posterior views, respectively; 40, apex of female abdomen, caudoventral view. Scales in mm. Lettering as in Fig. 16.