Hypoxys triangularis (Dallas, 1851) Nunes et al., 2020

Cunha, Eduardo Victor De Paiva & Fernandes, José Antônio Marin, 2022, New species of the Hypoxys triangularis group and the first contribution on the morphology of the internal genitalia of Hypoxys Amyot & Serville, 1843 (Hemiptera: Pentatomidae: Edessinae), Zootaxa 5168 (5), pp. 501-520 : 502-504

Hypoxys triangularis Group

( Figs. 1–12 )

Diagnosis. Body uniformly green with corium reddish-brown ( Fig. 10 ) (green with yellow spots in H. triangularis — see Nunes et al. 2020: Fig. 19E–F), and a median large yellow spot on the ventral surface. Species of the H. triangularis group also lack any transversal black stripe on pronotum and ventral surface, like in the other species groups of Hypoxys , except H. triangularis (see Nunes et al. 2020: Fig. 19E). Trichobothria with base yellowish ( Fig. 10F ). Male genitalia. Paramere (Pa) usually ax-shaped ( Fig. 1B ). Inner wall of pygophore laterally swollen ( Figs. 3B–C , 8 —black arrow). Ventral rim (Vr) with expansions slightly developed and rounded ( Fig. 4C ). Female genitalia ( Fig. 9 ). Valvifers VIII (Vf8) with mediolateral crest swollen (black arrow); outer lateral angle of the posterior margin (red arrow) rounded or ending in an acute projection.

Redescription. Head. Mandibular plates without spot ( Figs. 10 , 11 ). Antennae yellow with setae more densely distributed on antennomeres III, IV and V.

Thorax.Anterolateral margin of pronotum usually not punctured, except H. subrastratus (see Nunes et al. 2020: Fig. 19I) and H. saltensis sp. n. ( Fig. 10E ). Apex of humeral angle with margin brown ( Figs. 10 , 11 ). Pronotum and scutellum usually with brown punctures ( Fig. 10A ). Anterior margin of scutellum without yellow stripe, like the one found in some species of H. quadridens and H. oxyacanthus groups. Costal margin of corium with a black spot reaching approximately 1/3 of corial extension ( Figs. 10 , 11 ). Propleura with concolorous punctures concentrated on posterior half. Evaporatorium slightly whitish ( Figs. 10F , 11A ). Metasternal process with arms of anterior bifurcation receiving fourth and most of third rostral segment ( Fig. 10A ).

Abdomen. Dorsal surface with brown spots. Connexivum with two barely excavated areas ( Fig. 10C ) and usually not associated with dark spot (except H. triangularis ). Pseudosutures with or without adjacent dark green spot ( Figs. 10B , 11D ).

Male. Pygophore dorsally with brown to reddish brown spot occupying about 1/2 of the length of the pygophore; distal part of dorsal surface coarse ( Fig. 1A ). Superior process (Pc) of genital cup brown and positioned near to dorsal rim ( Fig. 2C ). Paramere directed posterolaterally ( Fig. 9 ); base with a swollen and rounded protuberance ( Fig. 9 , blue arrow). Proctiger (Proc) with posterior face triangular, elliptical or pentagonal, and bent ventrally ( Fig. 8 ).

Female. Valvifers VIII and Valvifers IX (Vf9) convex ( Fig. 2E ). Laterotergites VIII (La8) with margin black ( Fig. 9 ). Laterotergites IX (La9) with outer lateral margin sinuous, well projected beyond sclerite uniting laterotergites VIII; almost reaching level of laterotergites VIII ( Fig. 4E ). Capsula seminalis (Cs) with two thick projections of equal lengths ( Fig. 6D ); projections of capsula seminalis of the same width as pars intermedialis (Pi) ( Fig. 6F ).

Comments. Five new species are described into H. triangularis group. Therefore, the new composition of the group is: Hypoxys triangularis ; H. capito ; H. subrastratus ; H. myrtacivorus sp. n.; H. saltensis sp. n.; H. striatus sp. n.; H. curvatus sp. n. and H. ocanensis sp. n. The H. triangularis group has species associated with cultivated plants of the family Myrtaceae Juss. (Angiosperma; Myrtales ): H. triangularis associated the Eugenia uniflora L. (brazilian-cherry) and Psidium guajava (guava) ( Lima et al. 2010); H. subrastratus associated the Eugenia uniflora (brazilian-cherry) (data base Inaturalist; Fernandes pers. Comm.); H. myrtacivorus sp. n. associated the Myrciaria dubia (Kunth) McVaugh (camu-camu) ( Panduro et al. 2001), Eugenia malaccensis L. (red jambo) and Eugenia uniflora L. (see comments of H. myrtacivorus sp. n.). Parameres of this species group are also almost straight in dorsal view and never strongly curved laterally, characteristic shared with Hypoxys balteatus group (see in Mendonça et al. 2021). The internal genitalia of some Edessinae genera were described, but never compared or discussed in a comprehensive way ( Pantochlora vivida Stål, 1870 , ilustrated— Kumar (1969); Brachystethus Laporte, 1832 — Grazia & Barcellos (2003); Paraedessa Silva & Fernandes, 2013 — Silva et al. (2013); Ascra Say, 1832 — Santos et al. (2015); Plagaedessa Almeida & Fernandes, 2018 — Almeida et al. (2018); Pygoda Amyot & Serville, 1843 — Fernandes et al. (2018); Graziaedessa anastrephae Eger, 2021 , only the phallus described— Eger (2021); Edessa ovina group— Fernandes & Silva (2021)). The internal genitalia of species of Hypoxys have not been describe yet. This is the first attempt to compare and use internal genitalia to characterize the groups of species. Studying the internal genitalia of species belonging to the Hypoxys , we observed some characteristics that support Hypoxys and its groups of species. The female internal genitalia present the following characteristics for Hypoxys : distal part of vesicular area of the ductus receptaculi sclerotized ( Fig. 6E , yellow arrow); base of the capsula seminalis spherical and sclerotized ( Fig. 6D , green arrow); capsula seminalis dilated with thick projections well-developed ( Fig. 6B ); posterior annular crest more developed than anterior annular crest ( Fig. 6A ). The phallus of Hypoxys species have the phallotheca cylindrical and curved dorsoventrally ( Fig. 7 ). The differences observed between the species belonging to different groups of Hypoxys were: the H. quadridens ( Fig. 6A ) and H. oxyacanthus ( Fig. 6B ) groups share the projections of capsula seminalis wider and more dilated than the pars intermedialis. In H. triangularis ( Fig. 6D, E, F ) and H. balteatus ( Fig. 6C ) groups the projections of capsula seminalis are almost as wide as pars intermedialis. Groups H. quadridens and H. oxyacanthus share median portion of pars intermedialis thickened and spherical, while in H. triangularis group this structure is spherical or cylindrical, and in H. balteatus group the same structure is cylindrical. The H. quadridens group shows the base of capsula seminalis conical ( Fig. 6A , red arrow). Hypoxys oxyacanthus group has the globose base of capsula seminalis as wide as the segment X. A comparative study of the internal genitalia in all taxa of Edessinae can help to understand the evolution of the genitalia in the subfamily and add diagnostic characteristics to the genera.

Distribution ( Fig. 12 ). BRAZIL; FRENCH GUIANA; VENEZUELA; PARAGUAY; SURINAME; GUIANA; BOLIVIA; PERU; COLOMBIA, and ARGENTINA.

Key to species of the Hypoxys triangularis group

1. Pronotum with posterior smoky brown stripe; ventral surface of the body with small yellow calli (See Nunes et al. 2020: Fig. 19E–F).................................................................................. H. triangularis

1’. Pronotum without dark stripe; ventral surface of the body without yellow calli ( Figs. 10A , 11A )...................... 2

2. Male............................................................................................... 3

2’. Female..............................................................................................8

3. Proctiger strongly ( Figs. 1B , 3B , See Nunes et al. 2020: Fig. 11A–B ) or moderately excavated laterally ( Fig. 4D ).........4

3’. Proctiger shallowly excavated laterally ( Figs. 2D , 8B )........................................................ 7

4. Dorsal rim of pygophore medially notched (See Nunes et al. 2020 – Fig. 11A ). Superior process of genital cup subtriangular, almost the same size on swollen area on inner wall of pygophore ( Fig. 8C )............................ H. subrastratus

4’. Dorsal rim entire. Superior process of genital cup elliptic, bigger than swollen area on inner wall of pygophore ( Figs. 1B , 3B , 4B )................................................................................................ 5

5. Superior process of genital cup coarse in posterior view ( Fig. 3B ). Paramere spearhead-shaped ( Fig. 3D ).. H. saltensis sp. n.

5’. Superior process of genital cup smooth in posterior view ( Figs. 1B , 4B ). Paramere ax-shaped ( Fig. 1D , 4D )............. 6

6. Swollen area on inner wall globose, developed, close to posterolateral angles ( Fig. 8D ). Ventral rim with bottom of excavation convex ( Fig. 1C )..................................................................... H. myrtacivorus sp. n.

6”. Swollen area on inner wall narrow, slightly developed, contiguous to posterolateral angles ( Fig. 8E ). Ventral rim with bottom of excavation flat ( Fig. 4C )............................................................... H. curvatus sp. n.

7. Superior process of genital cup subtriangular, small, swollen in posterior view ( Fig. 2B ). Expansions of ventral rim hardly visible ( Fig. 2C ).......................................................................... H. striatus sp. n.

7’. Superior process of genital cup elliptic, narrow, smooth in posterior view ( Fig. 8B ). Expansions of ventral rim visible (See Nunes et al. 2020: Fig. 10C )...................................................................... H. capito

8. Valvifers VIII with outer lateral angle rounded ( Figs. 2E , See Nunes et al. 2020: Figs. 10D , 11D )..................... 9

8’. Valvifers VIII with outer lateral angle acute ( Figs. 1E , 4E , 5A )................................................ 11

9. Valvifers VIII with excavation in “V” (See Nunes et al. 2020: Fig. 10D ).................................. ... H. capito

9’. Valvifers VIII with excavation in “U” ( Figs. 2E , See Nunes et al. 2020: Fig. 11D )................................. 10

10. Valvifers VIII with mediolateral crest slightly swollen ( Fig. 9F ); median excavation narrow, clearly narrower than base of valvifers IX ( Fig. 2E ).................................................................... H. striatus sp. n.

10’. Valvifers VIII with mediolateral crest swollen ( Fig. 9C ); median excavation wide, almost as wide as base of valvifers IX (See Nunes et al. 2020: Fig. 11D )................................................................ H. subrastratus

11. Mediolateral crest of valvifers VIII carinated ( Fig. 5B )......................................... H. ocanensis sp. n.

11’. Mediolateral crest of valvifers VIII not carinated ( Fig. 8D, 8E )................................................ 12

12. Valvifers VIII with mesial borders forming a spiniform median projection ( Fig. 1E )............... H. myrtacivorus sp. n.

12’. Valvifers VIII with mesial borders not forming a spiniform projection. ( Fig. 4E )..................... H. curvatus sp. n.

Figures

FIGURE 1. Hypoxys myrtacivorus sp. n. Male (pygophore): A—dorsal view, B —posterior view, C—ventral view, D— posterolateral view. Female: E—genital plates. Acronyms: Dr—dorsal rim; Pc—superior process of the genital cup; Pa— parameres; Proc—proctiger; Vr—ventral rim; Vf8—valvifers VIII; Vf9—valvifers IX; Lat 8—laterotergites VIII; Lat 9— laterotergites IX; Va9—valvulae IX; X—tenth segment. Scale bars = 1 mm.

FIGURE 2. Hypoxys striatus sp. n. Male (pygophore):A—dorsal view, B —posterior view, C—ventral view, D—posterolateral view. Female: E—genital plates. Scale bars = 1 mm.

FIGURE 3. Hypoxys saltensis sp. n. Male (pygophore):A—dorsal view, B —posterior view, C—ventral view, D—posterolateral view. Scale bars = 1 mm.

FIGURE 4. Hypoxys curvatus sp. n. Male (pygophore):A—dorsal view, B —posterior view, C—ventral view, D—posterolateral view. Female: E—genital plates. Scale bars = 1 mm.

FIGURE 5. Hypoxys ocanensis sp. n. Female genital plates: A—ventral view, B—oblique view. Scale bars = 1 mm.

FIGURE 6. Internal female genitalia: A—Hypoxys trabeculus (Breddin, 1907) (H. quadridens group); B—H. oxyacanthus (Breddin, 1904) (H. oxyacanthus group); C—H. aspilogaster Mendonça et al., 2021 (H. balteatus group); D—H. triangularis (H. triangularis group); E—H. subrastratus (H. triangularis group); F—H. myrtacivorus sp. n. (H. triangularis group). Acronyms: aac—anterior annular crest; ch—chitinellipsen; cs—capsula seminalis; de—ductus receptaculi; vf9—valvifers 9; la9—laterotergite 9; pac—posterior annular crest; pi—pars intermedialis; tvi—thickening of vaginal intima; x—abdominal segment X. Scale bars = 1mm.

FIGURE 7. Phallus A—H. triangularis; B—H. subrastratus; C—Hypoxys myrtacivorus sp. n. Acronyms: ph—phallotheca; vs—vesica. Scale bars = 1mm.

FIGURE 8. Male genital capsule in posterolateral view, swollen area on inner wall of the pygophore indicated by the arrow: A—Hypoxys triangularis; B—H. capito; C—H. subrastratus; D—H. myrtacivorus sp. n.; E—H. curvatus sp. n.; F—H. striatus sp. n. Scale bars = 1mm.

FIGURE 9. Female genital plates in oblique view, mediolateral crest swollen on valvifers VIII indicated by the arrow: A— Hypoxys triangularis; B—H. capito; C—H. subrastratus; D—H. myrtacivorus sp. n.; E—H. curvatus sp. n.; F—H. striatus sp. n. Scale bars = 1mm.

FIGURE 10. Dorsal and ventral view. A–B Hypoxys myrtacivorus sp. n.; C–D H. striatus sp. n.; E–F H. saltensis sp. n. Scale bars = 5mm.

FIGURE 11. Dorsal and ventral view. A–B H. curvatus sp. n.; C–D Hypoxys ocanensis sp. n. Scale bars = 5mm.

FIGURE 12. Distributional map of the species H. triangularis group.