Xynocoris Garbelotto & Campos,

Garbelotto, Thereza De A., Campos, Luiz A. & Grazia, Jocelia, 2014, Xynocoris, new genus of Ochlerini from Central and South America (Hemiptera: Pentatomidae: Discocephalinae), Zootaxa 3869 (3), pp. 281-305: 282-284

publication ID

http://dx.doi.org/10.11646/zootaxa.3869.3.4

publication LSID

lsid:zoobank.org:pub:D4638897-09A5-4699-B2B9-CE079F3D9797

persistent identifier

http://treatment.plazi.org/id/D5668C50-FFC4-3A66-B3C7-7B447393C598

treatment provided by

Plazi

scientific name

Xynocoris Garbelotto & Campos
status

gen. nov.

Xynocoris Garbelotto & Campos  gen. nov.

Etymology. The epithet refers to the cryptic morphology of the species. Greek: xynos (m.), common.

Type species. Xynocoris parvus ( Distant, 1880) 

Description. Body oval, general color light brown to dark brown, sometimes with pale areas on pronotum and hemelytra. Punctures brown to black, forming wrinkles on posterior half of pronotum and on disc of scutellum. Antennae four- or five-segmented, with sexual dimorphism.

Head wider than long, declivous; punctures may be confluent forming wrinkles from base of mandibular plates to posterior margin of head; vertex without punctures, flat to slightly tumid. Mandibular plates longer than clypeus, apices convergent, lateral margin sinuous and reflected. Anteocular processes small and obtuse to projected as a spine. Antennal tubercles with lateral spine, partially visible from above or completely covered by the anteocular processes. Antennae four- or five-segmented. Eyes on a short peduncle in some species; ocelli posterior to hind margin of eyes. Ventrally with 1 + 1 longitudinal carinae posterior to the eyes, concolorous with the surface to yellowish, delimiting the base of eyes and gula. Gula slightly depressed, width equivalent to the eye diameter; punctures evenly distributed. Bucculae elevated, evanescent posteriorly, not attaining posterior margin of head, with triangular anterior tooth in some species. Rostrum attaining urosternites III to V; first segment reaching prosternum, second segment the longest; insertion of first segment of labium posterior to anterior limit of eyes.

Pronotum wider than long, anterior half declivous; punctures deep and confluent, forming wrinkles posterior to cicatrices. Cicatrices flat or with median tubercle. Anterior margin sinuous, concave in the median third. Anterior angle of pronotum with small projection directed anterolaterally, exceeding lateral margin of eyes for at least half the diameter of eye. Anterolateral margins subrectilinear to convex, reflected; posterolateral margins subrectilinear to convex; posterior margin subrectilinear. Scutellum longer than wide, reaching connexival segment V; punctures confluent, wrinkles more dense on disc; apex without punctures or punctures inconspicuous. Foveae at basal angles black, shallow, and punctured. Corium longer than scutellum, reaching connexival segment VI; punctures deeper and denser on exocorium; 1 + 1 yellowish spot at apex of radial vein, equivalent at least to the ocellar diameter, sometimes inconspicuous. Membrane not surpassing apex of abdomen, bearing six to nine veins not forming cells. Pro-, meso-, and metapleura with punctures evenly distributed. Prosternum sulcate, meso- and metasternum with median carinae along entire length. Mesopleural evaporatorium narrow, occupying a thin area along the posterior margin of mesopleura; metapleural evaporatorium occupying half the width of metapleura, lateral margin subrectilinear. Peritreme spout. Legs light brown, usually contrasting with the body. Tibiae sulcate dorsally. Third segment of metatarsi of males and females depressed dorsally.

Connexivum exposed from segments III to VII, narrow lateral strip without punctures. Abdomen with punctures, denser on lateral third, inconspicuous or absent on central disc; longitudinal furrow inconspicuous on median third of sternites III to V. Trichobothria lateral to imaginary line tangential to spiracles. Spiracles black; sometimes a yellowish maculae, somewhat elevated before the spiracles, on III—VII sternites present (fig. 8 A – D, F – H).

Male. Antennae: third to last segment the widest; also wider than corresponding segment in females. Articular membrane along the posterior margin of urotergite VII uniformly concave.

Genitalia. Pygophore barrel shaped ( fig. 5 A – LView FIGURE 5). Posterolateral angles excavated, narrowed by the projection of inferior layer of ventral rim; apices round and tumid ( fig. 5 AView FIGURE 5 –L—pa). Dorsal rim concave with 2 + 2 small arched projections laterad to segment X: anterior pair laminate, posterior pair tumid. Inferior layer of ventral rim with 1 + 1 thin subtriangular projections over genital cup, directed dorsoanteriorly perpendicular to frontal plane of pygophore, their apices round to tumid ( fig. 5 A – C, GView FIGURE 5 –I—pil). Superior layer of ventral rim bearing lighter lobular areas beneath the projection of inferior layer ( fig. 4 CView FIGURE 4 –D—arrow). Inferior layer of ventral rim with a median conical projection truncate at apex ( fig. 5 D – F, JView FIGURE 5 –L—cp), sometimes continued laterally as a low carinae directed to posterolateral angles of pygophore. Median third of ventral rim uniformly excavated or emarginated ( fig. 5 D – F, J – LView FIGURE 5). Segment X subrectangular, exceeding the posterior limit of inferior layer of ventral rim; basal half membranous, lateral margins subrectilinear to sinuous with 1 + 1 ventrolateral carinae bearing tufts of short setae; anal opening apical ( fig. 5 A – C, G – IView FIGURE 5); ventral genital opening in a longitudinal slit ( fig. 5 D – F, J – LView FIGURE 5). Parameres short and slender, ventral to segment X ( fig. 5 D – F, JView FIGURE 5 –L—par), sinuous in lateral view, margins subparallel ( fig. 6 A – LView FIGURE 6); head subtriangular, usually visible from the ventral opening of pygophore, bearing tuft of long setae.

Phallus ( fig. 7 A – PView FIGURE 7). Phallotheca globose (ph); lateral projection broad and spatulate (lph); dorsal and ventral apical processes conical (dp), ventral inconspicuous. Vesica narrowed at base (v); 1 + 1 dorsal processes (vp) directed anterodorsally lateral to ductus seminis distalis. Ductus seminis distalis (ds) sinuous or twisted, helical, surpassing the base of phallotheca, apex in gutter.

Female. Antennal segments uniformly wide.

Genitalia. Gonocoxites 8 subrectangular (fig. 8 A –I—gc 8), posterior margin subrectilinear to sinuous; posterolateral angles obtuse, or rounded projecting over the base of laterotergites 8; disc with median callus; sutural margins juxtaposed. Laterotergites 8 (fig. 8 A –I—la 8) triangular, posterior margin subrectilinear; spiracles on small callus posterior to lateral angle of gonocoxites 8. Exposed portion of gonocoxites 9 diamond-shaped (fig. 8 A –I—gc 9); longitudinal suture present or not; inner portion with anterior margin emarginated ( fig. 9 AView FIGURE 9 –G—gc 9). Laterotergites 9 subtriangular, apices round (fig. 8 A –I—la 9) reaching the band connecting laterotergites 8; mesial and lateral margins on the same plane; basal lateral angle excavated (fig. 8 A –I—d 9); inner portion with anterior margin subrectilinear ( fig. 9 AView FIGURE 9 –G—la 9). Pars comunis with conical microsculptures. Gonapophyses 8 and 9 with folds bearing conical microsculptures ( fig. 4 AView FIGURE 4 –B—arrow). Thickenings of gonapophyses 9 present with lateral projections ( fig. 9 AView FIGURE 9 –G—tg 9). Thickening of vaginal intima subrectangular to subtriangular ( fig. 9 AView FIGURE 9 –G—vi). Ring sclerites (chitinellipsen; fig. 9 AView FIGURE 9 –G—rs) laterad to thickening of vaginal intima. Ductus receptaculi ( fig. 9 AView FIGURE 9 –G—dr) anterior to vesicular area as wide as or wider than median duct of vesicular area. Median duct enlarged at base ( fig. 9 AView FIGURE 9 –G—md); inner duct narrowing towards the apex ( fig. 9 AView FIGURE 9 –G—id). Length of tubular portion of ductus receptaculi posterior to the vesicular area equals at least one third the length of vesicular area. Pars intermedialis subcylindrical ( fig. 9 AView FIGURE 9 –G—pi); annular ridges convergent. Capsula seminalis hemispherical; projections long, slender, sometimes bifid at apex ( fig. 9 AView FIGURE 9 –G—cs).

Comments. Xynocoris  is proposed based on two synapomorphies, the presence of long, projected, and acute anteocular processes, and apices of posterolateral angles of pygophore tumid ( Garbelotto et al. 2013). Other diagnostic characters are the general body shape, the dorsal rim of the pygophore with projections laterad to segment X, the inferior layer of ventral rim with subtriangular projections over the genital cup, the shape of the ventral rim, the globose phallotheca, and the shape of the dorsal processes of vesica; the subrectangular gonocoxites 8 with median callus on disc, the subtriangular laterotergites 9, the inner portion of gonocoxites 9 with emarginated anterior margin, and the thickenings of gonapophyses 9 present and with lateral projections. The species of Xynocoris  gen. nov. can be easily differentiated by characteristics of both male and female genitalia.

Distribution. Costa Rica, Panama, Venezuela, Trinidad y Tobago, Suriname, Brazil, Ecuador, Bolivia, Paraguay and Argentina.

Key to the species of Xynocoris  gen. nov.

1 Antennae four-segmented.............................................................................. 2

- Antennae five-segmented.............................................................................. 6

2 Mandibular plates exceeding clypeus by twice or more the diameter of ocellus; rostrum short, second segment reaching between pro- and mesocoxae, apex attaining urosternite III; cicatrices of pronotum with median tubercle.................................................................................... Xynocoris tuberculatus  sp. nov. ( fig. 2 BView FIGURE 2).

- Mandibular plates exceeding clypeus by a distance equivalent to the diameter of ocellus; other characteristics variable..... 3

3 Body length greater than 10mm; anterolateral margins of pronotum concave, crenulated; anterior pronotal angles with projections lateral to the eyes; gula concolor with head, yellowish maculae before spiracles absent.................................................................................................. Xynocoris crinitus  sp. nov. ( fig. 3 DView FIGURE 3).

- Body length less than 10mm; anterolateral margins of pronotum subrectilinear to slightly concave, smooth; anterior angles with projections posterior to the eyes; gula yellowish and yellowish maculae before spiracles present.................. 4

4 Anteocular processes small, obtuse; abdomen smooth with shallow punctures on lateral third; overall color light brown............................................................................. Xynocoris lucidus  sp. nov. ( fig. 3 CView FIGURE 3).

- Anteocular processes acute, attaining half the width of eye; abdomen with shallow, inconspicuous punctures between lateral margins and spiracles; overall color brown.................................................................. 5

5 Body oval, brown; anterolateral margins of pronotum reflected, anterior half expanded laterally........................................................................................... Xynocoris meridionalis  sp. nov. ( fig. 3 AView FIGURE 3).

- Body oval elongated, coppery brown; anterolateral margins of pronotum subrectilinear, not reflected or expanded................................................................................. Xynocoris cupreus  sp. nov. ( fig. 3 BView FIGURE 3).

6 Eyes placed on short peduncle........................................................................... 7

- Eyes juxtaposed to margin of head, without peduncle........................................................ 9

7 Rostrum short, apex lying on urosternite III.................................... Xynocoris recavus  sp. nov. ( fig. 2 CView FIGURE 2).

- Rostrum long, attaining or surpassing urosternite IV......................................................... 8

8 Anterolateral margins of pronotum strongly reflected, anterior half expanded laterally; anterior angles of pronotum with projections lateral to the eyes; abdomen setose.................................... Xynocoris calosus  sp. nov. ( fig. 2 FView FIGURE 2).

- Anterolateral margins of pronotum slightly and uniformly reflected; anterior angles of pronotum with processes posterior to the eyes; abdomen glabrous................................................ Xynocoris parvus (Distant)  ( fig. 2 AView FIGURE 2).

9 Body oval elongated; anterolateral margins of pronotum concave; scutellum bearing 1 + 1 yellowish calluses near the fovea........................................................................ Xynocoris insularis  sp. nov. ( fig. 2 DView FIGURE 2).

- Body oval; anterolateral margins of pronotum subrectilinear; scutellum without callus or spots on anterior margin................................................................................... Xynocoris egeri  sp. nov. ( fig. 2 EView FIGURE 2).