Ischnopelta cristulata 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 : 135-138

Ischnopelta cristulata Rosso & Campos , sp. n. ( Figs. 5H , 24–25 )

Etimology. The epithet refers to the presence of a transverse small crest on the ventral surface of parameres. Latin: cristula = small crest.

Type locality. BRAZIL, Mato Grosso, Rondonópolis [-16.4679, -54.6414] .

Holotype. Male. BRAZIL, Mato Grosso, Rondonópolis, XI.1963, M. Alvarenga. Deposited at Museu de Entomologia Pe. Jesus Santiago Moure, Universidade Federal do Paraná ( DZUP), Curitiba (PR), Brazil.

Paratypes. 4 males and 14 females. BRAZIL, Rondônia, Vilhena , 1 female, 21. II.1961, J. & B. Bechyné, [-12.7363, -60.1309], ( MPEG); Mato Grosso, Campo Novo do Parecis, Utiariti ( Papagaio river ), 2 males and 6 females, 7.VIII.1961, K . Lenko, [-13.0215, -58.2870], ( UFRG) , 1 female, 22–31.X.1966, K. Lenko, [-13.0215, - 58.2870], ( UFRG); Rondonópolis , 2 males and 2 females, XI.1963, M. Alvarenga, [-16.4679, -54.6414], ( DZUP); Mato Grosso do Sul, Campo Grande, Indubrasil ( N. O. B zone), 4 females, 17.X.1938, Exp. Instituto Oswaldo Cruz, [-20.4775, -54.762222], ( FIOC) .

Description. The overall somatic morphology is as described for I. scutellata , except for the following features. Head. Labrum inserted anterior to half the distance between the anterior margin of the eyes and the apex of mandibular plates. Antennae dark yellowish, segments IV and V slightly darker than others, some with minute punctures on segments II and III; segments ratio: I<II<III<IV<V.

Thorax. Hemelytra: corium as long as scutellum; conspicuous spot at apex of radial vein. Membrane with veins ramified. Setae on posterodorsal margin of protibiae as long as the others.

Abdomen. Dark spots at the lateral of urosternites subequal, both narrow; urosternite VII unarmed.

Male. Apical margin of membrane of hemelytra convex. Median portion of posterior margin of urosternite VII concave; urosternite VII not reaching anteriorly the imaginary line connecting the spiracles of urosternite V.

Genitalia. Pygophore with dorsal rim concave and median portion subrectilinear ( Fig. 24C , dr); ventral rim slightly concave ( Fig. 24D , vr). Posterolateral angles 1.24 times longer than the rest of the pygophore, base perpendicular and apex oblique to the frontal plane, convergent from the base ( Fig. 24C–E , pla). Short setae on distal half of ventral and lateral surface of pygophore, and on outer and inner surfaces of posterolateral angles; long setae on ventral rim, except on median portion, and on ventral and apical magins of posterolateral angles. Segment X slightly wider than long, not reaching the apex of posterolateral angles and parameres; rounded; apical margin flat and membranous, lateral margins convex, more sclerotized and covered by long setae; median portion membranous, covered by short setae ( Figs. 24C–E, X; 24L–M ). Parameres falciform, flat, surpassing the apical margin of segment X, and reaching the apex of posterolateral angles; subparallel to the frontal plane; proximal portion of the outer margin slightly concave, apical portion strongly convex; inner margin sinuous, distal portion strongly escavated and with an apical aculeiform process, convergent and ventrolaterally directed; apical margin convex; ventral surface with a transverse crest delimiting the apical region ( Fig. 24G , vcp); setae covering the crest and the area posterior to it ( Figs. 24D , pa; 24F–I). Cup-like sclerites externally visible and with convergent apices ( Fig. 24D , cls). Phallus: proximal 2/3 of vesica dorsally convex and ventroposteriorly directed, base as wide as apical margin of phallotheca, gradually narrowing posteriorly, expanded ventrally; distal 1/3 sinuous; secondary gonopore ventroposterior and beveled ( Fig. 24J–K ).

Female. Membrane of hemelytra not reaching the posterior margin of mediotergite VIII, posterior margin convex; median portion of subrectilinear; median portion of posterior margin of urosternite VII convex; posterior margin of mediotergite VIII and projections of urosternite VII ( Fig. 25C , mpr) as described for I. scutellata .

Genitalia. Valvifers VIII wider than long; posterior margin subrectilinear and slightly oblique to the median line, sutural margins subrectilinear and folded dorsally; surface dark yellowish with punctures and brown blotches; setae on distal portion of sutural margins and on median half of posterior margin ( Figs. 5H ; 25C , vf8). Valvifers IX covered by valvifers VIII, lateral margin convex; setae on mid-basal portion of ventral surface ( Fig. 25D , vf9). Laterotergites IX not reaching the posterior margin of mediotergite VIII; lateral margin subrectilinear; setae on mid-basal portion of lateral margin and ventral surface ( Fig. 25C–D , la9). Thickening of vaginal intima wider than long; distal margin more sclerotized and slightly concave; lateral margins convex, broad mid-basal area membranous ( Fig. 25D , vi). Vesicular area: anterior portion to the collar 1/9 of posterior portion, median duct anterior to the collar with slight proximal widening ( Fig. 25D , mdp); median duct posterior to the collar with proximal widening ( Fig. 25D , md); inner duct curved, almost coiled, in the proximal widening ( Fig. 25D , id). Distal ductus receptaculi 0.5 times the length of vesicular area posterior to the collar ( Fig. 25D , drd, drp). Pars intermedialis cylindrical ( Fig. 25D , pi); annular crests perpendicular to the pars intermedialis, the distal 1/3 larger than proximal one ( Fig. 25D , dac, pac). Capsula seminalis globose with a long filiform lateral projection directed to the pars intermedialis ( Fig. 25D , cs, pr).

Measurements: Table 9.

Distribution. Brazil (Rondônia, Mato Grosso, Mato Grosso do Sul) ( Fig. 7 ).

Comments. Ischnopelta cristulata is distinguished from I. coralinae sp. n., I. impunctata sp. n., I. luteicornis , I. parvula sp. n., I. pellucidula sp. n. and I. ruckesi sp. n., by the subrectilinear and transverse crest on the ventral surface of parameres ( Figs. 18D, G , vcp; 24G, vcp; 29D, G, vcp; 31D, G, vcp; 39D, vcp; 43B, E, vcp; 44D, G, vcp). See comments in I. coralinae sp. n..

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 18. Ischnopelta coralinae 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: amp, apical margin; cls, cup like sclerites; dr, dorsal rim; pa, parameter; ph, phalloteca; pla, posterolateral angle; vcp, ventral crest; vr, ventral rim; vs, vesica; X, segment X.

FIGURE 24. Ischnopelta cristulata 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: cls, cup like sclerites; dr, dorsal rim; pa, parameter; ph, phalloteca; pla, posterolateral angle; vcp, ventral crest; vr, ventral rim; vs, vesica; X, segment X.

FIGURE 25. Ischnopelta cristulata 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.