Euschistus (Lycipta) riograndensis Weiler & Grazia

Weiler, Luciana, Ferrari, Augusto & Grazia, Jocelia, 2011, Contributions to the knowledge of Euschistus (Lycipta) with the description of E. (L.) riograndensis sp. nov. (Hemiptera: Heteroptera: Pentatomidae: Pentatominae: Carpocorini), Zootaxa 3067, pp. 59-64 : 60-64

Euschistus (Lycipta) riograndensis Weiler & Grazia , sp. nov.

( Figs. 1–5 , 8–9, 11–15 )

Etymology. The species is named for the type locality.

Type locality. São Francisco de Paula, Rio Grande do Sul, Brazil.

Description. Male. Color: Dorsal surface (fig. 1) light to dark castaneous; ventral surface mostly dark castaneous (fig. 2). Ferruginous punctures on dorsal and ventral sides more numerous on abdomen and coarsely on thoracic segments. Antennae ferruginous, clear rings at base of segments III to V. Scutellum base angles with small ferruginous fovea, apex with 1+1 ferruginous spots. Segments of connexivum with dark round spot at base and apex. Legs light castaneous with coarse dots dark castaneous to ferruginous on femur and tibia. Tarsi immaculate, apical segment darkened. Spiracles luteous.

Clypeus acuminate, subequal in length to juga. Anterolateral margins of pronotum denticulate; humeral angles rectilinear less projected than in E. machadus . Pronotum cicatrices with a subcalloused spot at posterior margin, concolorous with pronotum. Posterolateral angles of urosternites less projected. Hemelytral veins reticulate.

Genitalia. Pygophore (figs. 3–5, 8) very similar to E. machadus differing in the size and proportion of the pygophoral structures as follows: superior process of dorsal rim (tumescence of Rolston 1982), in the area folded toward genital capsule, broader than in E. machadus (figs. 6–7); median third of dorsal rim slightly concave. Paramere head scythe-like, folded with foot in a larger angle than in E. machadus ; paramere foot subquadrangular, smaller than in E. machadus (figs. 9–10). Phallus: posterolateral angles of phallotheca developed (fig. 11); processus phallothecae thickened at base, divergent, almost attaining apex of processus vesicae (fig. 11–12). Conjunctiva wide, mostly hyaline, except the conjunctival appendages. Processus vesicae well developed, sclerotized, forming a spout where the ductus seminis distalis rests (fig. 12); ductus seminis distalis forming a spiral with at least two and a half turns (fig. 13). Secondary gonopore spatulate opening up towards processus vesicae (fig. 13).

Measurements (n= 13): total length 7.5 (7.14–7.83); head length 1.99 (1.9–2.09); head width 2.0 (1.92–2.05); length before eyes 1.06 (1.03–1.1); interocular width 1.25 (1.1–1.29); eye width 0.34 (0.32–0.38); antennal segments length: I 0.54 (0.47–0.57); II 0.79 (0.6–0.85); III 0.86 (0.79–0.95); IV 1.07 (0.98–1.2); V 1.3 (1.1–1.39); pronotum length 2.02 (1.9–2.13), pronotum width 4.76 (4.4–4.96); pronotum width with spine 5.6 (5.44–5.76); scutellum length 3.34 (3.12–3.51); scutellum width 3.33 (3.2– 3.51); abdomen length till VII segment 3.48 (3.2– 3.67); abdomen width 5.06 (4.88–5.28).

Female. Genitalia. Gonocoxites 8 (gc8) with sutural margins sinuate, overlapping (fig. 14); sutural angles with dense hairiness. Posterior margins of gonocoxites 8 indented where anterolateral angles of gonocoxites 9 (gc9) fit; gc9 with median sulcus, with dense hairiness, forming an obtuse angle with X segment. Laterotergites 9 (la9) just attaining band uniting dorsally laterotergites 8 (la8). Posterior margins of laterotergites 8 slighted projected posteriorly (fig. 14). Gonapophyses 8 quadrangular. Chitinellipsen present. Anterior thickening of vaginal intima bubblelike, longer than wide, posterior thickening ring-like (fig.15). Ductus receptaculi before vesicular area longer than this area, anterior portion in a funnel-like thickening; ductus receptaculi, adjacent to anterior annular flange, dilated (fig. 15). Pars intermedialis tubular, simple; capsula seminalis globose, teeth absent (fig. 15).

Measurements (n = 20): total length 7.89 (7.42–8.21); head length 2.03 (1.93–2.14); head width 2.03 (1.99– 2.09); length before eyes 1.1 (1.06–1.15); interocular width 1.32 (1.25–1.39); eye width 0.32 (0.3–0.36); antennal segments length: I 0.54 (0.51–0.64); II 0.8 (0.72–0.93); III 0.84 (0.79–0.91); IV 1.02 (0.95–1.14); V 1.28 (1.14– 1.38); pronotum length 2.12 (2.01–2.28), pronotum width 4.98 (4.64–5.2); pronotum width with spine 5.82 (5.6– 6.32); scutellum length 3.53 (3.27–3.78); scutellum width 3.51 (3.23– 3.78); abdomen length till VII segment 3.72 (3.51–3.92); abdomen width 5.47 (5.04–5.84).

Distribution. Brazil: Rio Grande do Sul (Esmeralda, São Francisco de Paula, Caxias do Sul, Caçapava do Sul, Pelotas).

Type material. Holotype ♂, BRAZIL, Rio Grande do Sul: São Francisco de Paula FLONA, 15.III.2008, L. Weiler col. ( MCNZ). Alotype ♀, same locality as holotype, 01.II.2007, L. Weiler & B. B. Fürstenau col. ( UFRG). Paratypes. Esmeralda ( Estação Ecológica de Aracuri ), 2♀, 18–19.III.1981, J. Grazia col. ( UFRG); same locality as holotype, ♂ ♀, 23.I.1959, Pereira, Ditadi, Petersen, Meyer & Volkmer leg. ( UFRG); 13 3♀, 17–19.XII.2005, V. C. Matesco & P. R. S. Bunde col. ( UFRG); 2♀, 29.I.2006, J. L. C. Bernardes col. ( UFRG); ♂ ♀, 08.IV.2006, A. Ferrari & L. Weiler col. ( AMNH); ♂, 09.VI.2006, V. C. Matesco col. ( UFRG); ♀, 31.I.2007, L. Weiler & B. B. Fürstenau col. ( UFRG); 23 2♀, 18.III.2007, C. F. Schwertner, L. Weiler & J. L. C. Bernardes col. ( UFRG); ♂, 16.III.2008, L. Weiler col. ( UFRG); 23, 06.III. 2010, L. Weiler col. ( UFRG); Caxias do Sul ( Vila Oliva ), ♀, 19.II.1954 ( MGAP), ♀, 16.I.1960 ( MGAP). Caçapava do Sul ( Pedra do Segredo ), ♀, 05.IV.2004, Bunde, Ferrari & Ely e Silva col. ( UFRG); Pelotas, ♀, X.1995, M. Schiower leg. ( UFRG).

Comments. E. riograndesis sp. nov. is very close to Euschistus (Lycipta) machadus , differing from this species by the proportion of the genitalia structures in both sexes, these being smaller in the new species. Rolston (1982) mentioned the presence of three pairs of species in the subgenus, where the genitalia are virtually identical (sic) ( E. aceratos and E. cribrarius , E. circumfusus and E. imitator , E. triangulator and E. picticornis ); the genitalic similarity among those species arouses suspicion that the forms may represent disjunct variation of single species ( Rolston 1982). On the same line of thinking, E. machadus and E. riograndensis may form the fourth pair; E. machadus is distributed in southeastern Brazil (Rio de Janeiro and São Paulo, according labels of Rolston’s type specimens), whereas E. riograndensis occurs in southern Brazil (Rio Grande do Sul).

Figures

FIGURES 1 – 7. Euschistus (Lycipta) riograndensis sp. nov. 1 – 5: 1, dorsal view; 2, ventral view; 3 – 5 pygophore, posterior, dorsal and ventral views, respectively. Euschistus (Lycipta) machadus 6 – 7: pygophore, posterior and ventral views, respectively. (bt, bristles tuft; par, parameres; spdr, superior process of dorsal rim; vr, ventral rim; X, tenth segment). Scales: Figs. 1 – 2 = 2 mm; 3 – 7 = 1 mm.

FIGURES 8 – 13. Euschistus (Lycipta) riograndensis sp. nov. 8, 9, 11 – 13: 8, pygophore, posterior view; 9, right paramere, lateral views; 11 – 13 phallus, posteroventral, anterodorsal, and lateral views, respectively. Euschistus (Lycipta) machadus: 10, right paramere, lateral views. (aa, articulatory apparatus; cj, conjunctiva; dc, dorsal connective; ds, ductus seminis; dsd, ductus seminis distalis; par, parameres; pht, phallotheca; pc, processus capitati; prpht, processus phallothecae; prv, processus vesicae; spdr, superior process of dorsal rim; X, tenth segment). Scales: Figs. 8 = 1 mm; 9 – 13 = 0, 5 mm.

FIGURES 14 – 15. Euschistus (Lycipta) riograndensis sp. nov.: 14, female genital plates; 15, female ectodermal ducts. (aaf, anterior annular flange; ch, chitinellipsen; cs, capsula seminalis; dr, ductus receptaculi; e, spiracle; g 9, gonapophyses 9; gc 8, gonocoxites 8; gc 9, gonocoxites 9; la 8, laterotergites 8; la 9, laterotergites 9; pi, pars intermedialis; thi, thickening of vaginal intima; va, vesicular area; X, tenth segment). Scales: Figs. 14 = 1 mm; 15 = 0, 5 mm.