Ischnopelta guarani Rosso & Campos

Rosso, Pedro & Campos, Luiz Alexandre, 2021, Revision of Ischnopelta Stål, 1868 with the description of twenty new species (Hemiptera: Pentatomidae: Discocephalinae), Megataxa 6 (2), pp. 96-184 : 141-144

Ischnopelta guarani Rosso & Campos , sp. n. ( Figs. 5S , 27–28 )

Etymology. The epithet is a tribute to the Guarani, a native people of South America, in whose original lands occurs the species.

Type locality. ARGENTINA, Corrientes, Laguna Brava [-27.4957, -58.6441] .

Holotype. Male. ARGENTINA, Corrientes, Laguna Brava (7 km E Corrientes, Route 5), 18.I.1989, C.W. & L.B. O’Brien & G. Wibmer. Deposited at Museo de La Plata , Universidade Nacional de La Plata ( MLPA), La Plata, Argentina.

Paratypes. 5 males and 2 females. BOLIVIA, Santa Cruz, Warnes (5 km SSE Warnes, Rio Selva Hotel ), 2 males, 20–21.X.2000, Morris & Wappers, [- 17.561111, -63.1994444], (J.E. Eger, Private collection) ; PARAGUAY, Alto Paraguai ( Grand Chaco, 250 km West Paraguay River), 1 male, 28. VI.1936, Alberto Schulze, [-23.366667, -59.6667], ( USNM); Central, Capiatá , 1 female, 15.I.1991, G. Arriagada, [-25.3500, -57.4167], (J.E. Eger, Private collection); Vila Elisa , 1 female, 2.XII.1939, Dernier Coll., [-25.3667, -57.6167], ( MLPA) ; ARGENTINA, Formosa, Laishi ( Riacho Tohué ), 2 males, 11.I.1939, Dernier Coll., [-26.408333, -58.258333], ( MLPA) .

Description. The overall somatic morphology is as described for I.scutellata ,except for the following features. Head. Antennae: segment I dark yellowish with brown blotches; segments II and II dark yellowish with brown punctures, ventral surface brown in some specimens; segments IV and V dark brown, proximal portion of segment IV dark yellowish with brown punctures in some specimens; segments ratio: I=II<III<IV<V.

Thorax. Scutellum: post-frenal lobe margins subparallel to the distal half. Hemelytra: conspicuous spot at apex of radial vein.

Abdomen pale-yellow; dark spots at the lateral of urosternites elongated and subtriangular, both wide and subequal in length.

Male. Apical margin of membrane of hemelytra convex; median portion of the posterior margin of urosternite VII concave; urosternite VII reaching anteriorly the imaginary line connecting the spiracles of urosternite V. Genitalia. Pygophore with dorsal and ventral rim slightly concave ( Figs. 27C , dr; 27D, vr). Posterolateral angles 1.4 times longer than the rest of the pygophore, perpendicular to the frontal plane and subparallel, apices slightly convergent, basal portion of the dorsal margin less sclerotized and folded to the interior of the pygophore ( Fig. 27C–E , pla). Setae in a band on the ventral rim, part of the lateral surface of the pygophore, and the lareral of the posterolateral angles; setae long on ventral rim and ventral margin of the posterolateral angles. Segment X longer than wide, not reaching the apex of the posterolateral angles and parameres; oval and weakly emarginated apically; lateral margins sclerotized and densely covered with long setae; mid-longitudinal portion membranous with short and sparse setae ( Figs. 27C–E, X; 27L–M ). Parameres claviform, oblique to the frontal plane, outer margin sinuous, convex on apical portion; inner margin sinuous, with a shallow cavity more sclerotized on the distal portion; apical margin convex forming a convergent process with the inner margin; dorsal and ventral surfaces sinuous, setae covering a narrow band on the sclerotized area of the inner margin ( Figs. 27D , pa; 27F–I). Cup-like sclerites externally visible, apices rounded and subparallel. Phallus: vesica sharply sinuous, proximal portion directed posteriorly, sharply curved ventroanteriorlly on median portion, and curved ventroposteriorlly on distal portion; basal portion laterally widened, short, dorsally flat, ventrally expanded, and gradually narrowing posteriorly; secondary gonopore beveled ( Fig. 27J–K ).

Female. Membrane of hemelytra not reaching the posterior margin of mediotergite VIII, posterior margin convex; posterior margin of mediotergite VIII and of & Campos, sp. n. specimens evaluated (n).

urosternite VII, and projections of urosternite VII as described for I. scutellata , but the later perpendicular to the surface of urosternite VII ( Fig. 28C , mpr). Genitalia. Valvifers VIII wider than long; posterior margin sinuous; sutural margins subrectilinear and dorsally folded; surface convex longitudinally, dark yellowish with brown punctures, setae on distal half of sutural margins and on posterior margin; longitudinal grooves narrow and shallow ( Figs. 5S ; 28C , vf8). Valvifers IX partially covered by valvifers VIII; lateral margin sinuous, midbasal portion of ventral surface without setae ( Fig. 28D , vf9). Laterotergites IX not reaching the posterior margin of mediotergite VIII; lateral margin convex; setae on median portion of lateral margin ( Fig. 28C–D , la9). Thickening of vaginal intima subcircular, median area broadly oval and membranous ( Fig. 28D , vi). Vesicular area anterior to the collar 1/8 of the posterior portion; median duct anterior to the collar with slight proximal widening ( Fig. 28D , mdp), median duct posterior to the collar with proximal and distal widening ( Fig. 28D , md), inner duct coiled in the proximal widening ( Fig. 28D , id). Distal ductus receptaculi narrower than proximal one, and 0.9 times the length of the vesicular area posterior to the collar ( Fig. 28D , drd, drp). Pars intermedialis barrel-shaped ( Fig. 28D , pi); annular crests directed to the ductus receptaculi, the proximal slightly larger than half the diameter of the distal one ( Fig. 28D , dac, pac). Capsula seminalis oval, with two filiform projections, one laterobasal long and sinuous, and the other shorter, midlateral, both directed to the pars intermedialis ( Fig. 28D , cs, pr).

Measurements: Table 11.

Distribution. Bolivia (Santa Cruz), Paraguay (Alto Paraguay, Central), Argentina (Formosa, Corrientes) ( Fig. 7 ).

Comments. Ischnopelta guarani sp. n. ( Fig. 27A– B ; 28A–B ) is similar to I. paiagua sp. n. ( Fig. 38A–B ), differing by the labrum inserted slightly posteriorly to half the distance between the anterior margin of the eyes and the apex of mandibular plates, the wider abdominal lateral blotches, and the shape of the parameres ( Figs. 27F–I ; 38F–I ).

Figures

FIGURE 5. Female genital plates.A, Ischnopelta scutellata (Signoret, 1851); B, Ischnopelta bechyneorum Rosso & Campos, sp. n.; C, Ischnopelta confusa Rosso & Campos, sp. n.; D, Ischnopelta magna Rosso & Campos, sp. n.; E, Ischnopelta cylindrata Rosso & Campos, sp. n.; F, Ischnopelta impunctata Rosso & Campos, sp. n.; G, Ischnopelta luteicornis (Walker, 1867); H, Ischnopelta cristulata Rosso & Campos, sp. n.; I, Ischnopelta coralinae Rosso & Campos, sp. n.; J, Ischnopelta ruckesi Rosso & Campos, sp. n.; K, Ischnopelta pellucidula Rosso & Campos, sp. n.; L, Ischnopelta parvula Rosso & Campos, sp. n.; M, Ischnopelta vellozia Rosso & Campos, sp. n.; N, Ischnopelta wigodzinskyi Rosso & Campos, sp. n.; O, Ischnopelta alalonga Rosso & Campos, sp. n.; P, Ischnopelta crassula Rosso & Campos, sp. n.; Q, Ischnopelta cordiformis Rosso & Campos, sp. n.; R, Ischnopelta montana Rosso & Campos, sp. n.; S, Ischnopelta guarani Rosso & Campos, sp. n.; T, Ischnopelta marginella Rosso & Campos, sp. n.. Abbreviations: vf8, valvifers VIII; la8, laterotergites VIII; la9, laterotergites IX; mpr, projection on the lateral third of posterior margin of sternite VII; t8, mediotergite VIII; X, segment X. Scale bars = 1 mm.

FIGURE 7. Distribution of Ischnopelta cordiformis Rosso & Campos, sp. n.; Ischnopelta crassula Rosso & Campos, sp. n.; Ischnopelta cristulata Rosso & Campos, sp. n.; Ischnopelta guarani Rosso & Campos, sp. n.; Ischnopelta impunctata Rosso & Campos, sp. n.; Ischnopelta luteicornis (Walker, 1867); Ischnopelta magna Rosso & Campos, sp. n..

FIGURE 27. Ischnopelta guarani Rosso & Campos, sp. n. Holotype male. A, dorsal view; B, ventral view, C–E, pygophore: dorsal, ventral, and posterior views respectively; F–I, parameters: dorsal, ventral, external and internal lateral views, respectively; J–K, phallus: lateral and dorsal views, respectively; L–M, segment X, dorsal and ventral views, respectively. Abbreviations: dr, dorsal rim; pa, parameter; ph, phalloteca; pla, posterolateral angle; vr, ventral rim; vs, vesica; X, segment X.

FIGURE 28. Ischnopelta guarani Rosso & Campos, sp. n. Female. A, dorsal view; B, ventral view; C, genital plates ventroposterior view (45º); D, internal genitalia. Abbreviations: cl, collar; cs, seminalis capsule; dac, distal annular crest; drd, distal ductus receptaculi; drp, proximal ductus receptaculi; id, internal duct; idp, proximal internal duct; la8, laterotergite VIII; la9, laterotergite IX; md, medium duct; mdp, proximal medium duct; mpr, projection on the lateral third of posterior margin of sternite VII; od, external duct; odp, proximal external duct; pac, proximal annular crest; pi, pars intermedialis; pr, projection; t8, mediotergite VIII; va9, valvulae IX; vf8, valvifer VIII; vf9, valvifer IX; vi, thickening of vaginal intima; X, segment X.

FIGURE 38. Ischnopelta paiagua Rosso & Campos, sp. n. Holotype male.A, dorsal view; B, ventral view; C–E, pygophore: dorsal, ventral, and posterior views respectively; F–I, parameters: dorsal, ventral, external and internal lateral views, respectively; J–K, phallus: lateral and dorsal views, respectively. Abbreviations: cls, cup like sclerites; dr, dorsal rim; pa, parameter; ph, phalloteca; pla, posterolateral angle; vr, ventral rim; vs, vesica; X, segment X.