Review of the sulcacitus group of Euschistus (Pentatomidae: Pentatominae: Carpocorini) with description of the internal female genitalia and a new species Bianchi, Filipe Michels Barão, Kim Ribeiro Grazia, Jocelia Zootaxa 2017 2017-12-06 4362 3 348 358 Bianchi & Grazia Bianchi & Barão & Grazia 2017 [151,757,1290,1317] Insecta Pentatomidae Euschistus GBIF Animalia Hemiptera 8 356 Arthropoda species tacitus sp. nov. Euschistus  ( Figs 5, 18–20, 26, 39–41, 57–59, 64)   Etymology:Epithet alludes to the external morphological similarities among the species of the  sulcacitusgroup and the new species. From taceo(Latin), to be silent, say nothing;  tacitus, meaning implied, unmentioned, in reference to a hidden species.   Distribution:Mexico (Chiapas, Veracruz); Costa Rica (Alajuela).   Typelocality: Lacanja, Chiapas, Mexico.    Typematerial: Holotype: MEXICO: ♂, Chiapas: Near Lacanjah,  310m, 16.77°N 91.13°W, 0  8 Jul 2009, D. Forero& G. Zhang[MEX09_SM_L15] / PTM00283( UNAM).  Paratypes: COSTA RICA: 1♂ 1♀ Alajuela: On hwy 4S of Mirador,  139m, 10.50°N 84.59°W, 0 9 Dec 2008, Weirauch & Forero[CR 0 8 L12] ( 1♂ UFRG) / PTM0285( 1♀ UFRG) (abdomen removed);  1♂ Guanacaste:  16 kmE of La Cruz, Hacienda Los Inocentes, 6.23.0 4, MV+UV light / COLLECTIO NACIONAL MUSEUM Praha, Czech Republic ( 1♂ NMPC);  1♂ Dos Rios,8.16.0 2 / COLLECTIO NACIONAL MUSEUM Praha, Czech Republic ( 1♂ NMPC);  1♀ Puntarenas: Hacienda Baru near to Dominical, 2.16.0 4 MV + UV light / COLLECTIO NACIONAL MUSEUM Praha, Czech Republic ( 1♀ MNRJ);  MEXICO: 1♂, 2♀ Veracruz: Rd between Cuetzalapan and Miguel Hidalgo,  361m, 18.37°N 95.01°W, 0  5 Jul 2009, D. Forero& G. Zhang[ MEX09_SM_L5] / PTM00287( 1♀ UFRG) (abdomen removed), PTM00288( 1♀ UFRG) (abdomen removed), PTM00289( 1♂ UCR);  1♂ Chiapas: Agua Fria, about 8.5 kmoff Hwy 186, 23m, 17.74°N 92.08°W, 0  6 Jul 2009, D. Forero& G. Zhang[ MEX09_SM_L7] / PTM00286( 1♂ UFRG) (pygophore removed);  3♂ 2♀ Near Lacanjah,  310m, 16.77°N 91.13°W, 0  8 Jul 2009, D. Forero& G. Zhang[ MEX09_SM_L15] / PTM0284( 1♂ UFRG), ( 1♂ 1♀ AMNH, 1♂ MNRJ 1♀ UNAM).   Description:Dorsal surface light brown; punctures black; punctures smaller on hemelytra than on remaining body parts. Humeri acutely projected laterally, but not developed as a spine, varying from light brown to reddish. Ventral surface greenish to light-yellow; punctures concolorous with the surface. Antennae uniformly yellow to orange ( Fig. 5). Head longer than wide; head punctate, punctures less dense on disc. Clypeus rounded apically; clypeus slightly longer than mandibular plates, rarely equal in length. Mandibular plates rounded apically. Rostrum reaching metacoxae. Anterolateral margins of pronotum toothed anteriorly and smooth posteriorly; teeth-like projections small, dark brown. Scutellum reaching abdominal segment V; anterolateral angles foveate. Punctures on scutellum and hemelytra smaller apically than basally. Membrane of hemelytra light brown; exocorium reddish in some specimens. Evaporatorium of metasternal glands not surpassing median line between ostiole and lateral margin of mesopleuron; spout peritreme. Presence of 1+1 dark spots at base of leg between epimeron and episternum of each pleurite, plus 1+1 at metepimeron medially. Legs concolorous with ventral surface of thorax; small dark dots on femora and tibiae. Abdomen: dorsally, disc of connexivum yellow, black stripes on anterior and posterior margins; ventrally, anterior angle with dark spot. Spiracles concolorous with abdominal sternites.  Male genitalia:Pygophore trapezoidal. Dorsal rim uniformly concave in dorsal view ( Fig. 18) median projection of dorsal rim long, sinuosity shallow; superior process of dorsal rim tooth-like. Ventral rim slightly sinuous, convex medially in ventral view ( Fig. 20). In posterior view, ventral rim protuberant medially; superior layer of ventral rim excavated in V-shape in posterior view ( Fig. 19). Paramere: margin connecting basal and apical process slightly concave; apical process somewhat spatulate at apex; middle process not developed ( Fig. 26).  Female genitalia:Posterior margin of gonocoxites VIII concave, posterolateral margin of gonocoxites VIII projected posteriorly, reaching middle of gonocoxites IX. Gonocoxites IX 2times wider than long, lateral margins strongly rounded; anterior margins of gonocoxites IX straight, posterior margin convex ( Fig. 57). Posterior region of ductus receptaculi proximalis straight, not dilated. Ductus receptaculi distalis dilated adjacent to anterior annular flanges. Pars intermedialis sclerotized at basal three-fourths ( Fig. 64).   Comments.The external morphology of the  sulcacitusgroup is homogeneous among its species. Some characteristics (e.g. coloration of dorsal and ventral surfaces of body, shape and length of humeral angles, and total body length) vary intraspecifically, making them useless to species diagnosis. Otherwise, the genitalic morphology provides valuable characters to species definition.  Euschistus tacitus  sp. nov.is more similar to  E. sulcacitusthan to the others species of the group by the posterior margin of pygophore slightly sinuate, convex mesially; and by the laterotergites IX not surpassing dorsal band that unites laterotergites VIII in posteroventral view.  Euschistus tacitus  sp. nov.can be distinguished from  E. sulcacitusby the inferior layer of ventral rim mesially tumescent in posterior view, and posterior margin of gonocoxites VIII mesially slightly concave. 2636405302 2009-07-08 UNAM D. Forero & G. Zhang Mexico 310 16.77 Near Lacanjah 768 -91.13 Near Lacanjah 8 356 PTM00283 1 1 Chiapas holotype 1703280306 2008-12-09 UFRG Weirauch & Forero Costa Rica 139 10.5 Alajuela 779 -84.59 On 8 356 PTM0285 4 1 1 Alajuela paratype 1703280307 NMPC Czech Republic Hacienda Los Inocentes 8 356 2 2 Guanacaste 1703280312 NMPC Czech Republic Dos Rios, 8 356 2 2 Praha 1703280308 MNRJ Costa Rica Puntarenas 8 356 2 2 Puntarenas 2636405301 1 ♂, 2 2009-07-05 UFRG, UCR D. Forero & G. Zhang Mexico Rd 361 18.37 Veracruz 765 -95.01 Cuetzalapan 8 356 MEX09_SM_L5, PTM00287, PTM00288, PTM00289 6 4 2 Veracruz 1703280304 2009-07-06 UFRG D. Forero & G. Zhang Mexico 17.74 Agua Fria 767 -92.08 Agua Fria 8 356 MEX09_SM_L7, PTM00286 25 25 Chiapas 1703280305 2009-07-08 UFRG, AMNH, UNAM D. Forero & G. Zhang Mexico 310 16.77 Near Lacanjah 768 -91.13 Near Lacanjah 8 356 MEX09_SM_L15, PTM0284, MNRJ 10 4 6 Jul 2009