Ischnopelta paiagua 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 : 163-164

Ischnopelta paiagua Rosso & Campos , sp. n. ( Fig. 38 )

Etymology. The epithet is in honor to the native people Paiaguás, currently extinct, that originally inhabited the Pantanal region in Brazil, where the species is distributed.

Type Locality. BRAZIL, Mato Grosso do Sul, Corumbá [-19.0167, -57.6500] .

Holotype. Male. BRAZIL, Mato Grosso do Sul, Corumbá, 1950, H. G. Barber Coll. Deposited at Museu de Zoologia da Universidade de São Paulo ( MZSP), São Paulo ( SP), Brazil.

Paratypes. 1 male. BRAZIL, Mato Grosso, Cáceres , 1 male, XII.1955, M . Alvarenga, [-16.0667, -57.6833], ( MNRJ) .

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

Thorax. Hemelytra: conspicuous spot at apex of the radial vein. Pro-, meso- and metasternum dark yellowish.

Abdomen. Dark spots at the lateral of urosternites narrow, subequal in length.

Male. Apical margin of membrane of hemelytra convex; median portion of posterior margin of urosternite VII subrectilinear; urosternite VII reaching anteriorly the imaginary line connecting the spiracles of urosternite V. Genitalia. Pygophore with dorsal and ventral rim slightly concave ( Figs. 38C , dr; 38D, vr). Posterolateral angles 1.5 times longer than the rest of the pygophore, perpendicular to the frontal plane, subparallel, apices slightly convergent; basal portion of dorsal margin less sclerotized and folded into the pygophore ( Fig. 38C–E , pla). Long setae on the ventral rim and ventral margin of the posterolateral angles, directed to the parameres.

Segment X longer than wide, not reaching the apex of the posterolateral angles and parameres; oval; apical margin weakly emarginated, lateral margins sclerotized and covered by dense, long setae; mid-longitudinal surface membranous with short and sparse setae ( Fig. 38C and E, X ). Parameres claviform, head slightly swollen, oblique to the frontal plane; outer margin sinuous, apical portion strongly convex; inner margin sinuous, apical portion more sclerotized and slightly convergent; apical margin narrow and convex; ventral surface sinuous, setae covering a band on the sclerotized area of the inner margin up to the apical margin ( Figs. 38D , pa; 38F–I). Cup-like sclerites externally visible, apices rounded and subparallel ( Fig. 38D , cls). Phallus: vesica sharply sinuous; proximal portion short, widened laterally, flat dorsally and expanded ventrally, weakly sclerotized and translucent in some points; median portion flat, more sclerotized than proximal portion, narrowing gradually; distal portion subcylindrical and gradually narrowing; secondary gonopore beveled ( Fig. 38J–K ).

Female. Unknown.

Measurements: Table 17

Distribution. Brazil (Mato Grosso, Mato Grosso do Sul) ( Fig. 8 ).

Comments. See comments in I. guarani sp. n..

Figures

FIGURE 8. Distribution of Ischnopelta marginella Rosso & Campos, sp. n.; Ischnopelta montana Rosso & Campos, sp. n.; Ischnopelta paiagua Rosso & Campos, sp. n.; Ischnopelta parvula Rosso & Campos, sp. n.; Ischnopelta pellucidula Rosso & Campos, sp. n.; Ischnopelta ruckesi Rosso & Campos, sp. n.; Ischnopelta vellozia Rosso & Campos, sp. n.; Ischnopelta wigodzinskyi Rosso & Campos, sp. n..

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.

Tables

TABLE 17. Measurements (mean, standard deviation, minimum and maximum) and number of Ischnopelta paiagua Rosso & Campos. sp. n. specimens evaluated (n).

Body structure	Measurements performed	n	Male Measurements (mm)	n	Female Measurements (mm)
Body	tl mw	2	7.12±0.22 (6.97–7.27) 3.84±0.09 (3.78–3.90)	–	– –
	hl		1.62±0.15 (1.51–1.73)		–
	cl		0.55±0.06 (0.50–0.59)		–
Head	hw	2	3.22±0.08 (3.16–3.28)	–	–
	iod		0.89±0.05 (0.85–0.92)		–
	ied		2.63±0.06 (2.58–2.67)		–
	pl		1.55±0.05 (1.52–1.59)		–
Pronotum	haw	2	3.47±0.12 (3.39–3.56)	–	–
	aaw		3.08±0.08 (3.02–3.14)		–
	sl		3.88±0.01 (3.87–3.88)		–
	fll		1.53±0.01 (1.52–1.53)		–
Scutellum	pfl	2	2.35±0.02 (2.34–2.36)	–	–
	bsw		2.29±0.08 (2.23–2.34)		–
	fcw		1.54±0.03 (1.52–1.56)		–
	I		0.47±0.01 (0.46–0.47)		–
	II	2	0.41±0.01 (0.41–0.42)		–
Antennae	III		0.70±0.02 (0.68–0.71)	–	–
	IV V	1	0.78 0.99		– –
	I		0.59±0.04 (0.56–0.61)		–
Labium	II III	2	1.25±0.03 (1.22–1.27) 0.50±0.01 (0.49–0.51)	–	– –
	IV		0.31±0.04 (0.29–0.34)		–

Legend: tl. total length; mw. maximum width (at the sternite III level); hl. head length; cl. clypeus length; hw. head width; iod. interocellar distance; ied. interocular distance; pl. pronotum length; haw. pronotum width at the level of humeral angles; aaw. pronotum width at the level of anterolateral angles; sl. scutellum length; fll. frenal lobe length; pfl. post-frenal lobe length; bsw. basal scutellum width; fcw; scutellum width at the level of frenal constriction; I. II. III. IV and V. antennal and labium segments length.