Trigava O'Brien , 1999

Song, Zhi-Shun, O'Brien, Lois B., Malenovsky, Igor, Deckert, Juergen & Bartlett, Charles R., 2024, Revision of the Neotropical genus Trigava O'Brien, 1999 (Hemiptera, Fulgoromorpha, Dictyopharidae, Nersiini), with descriptions of two new species from Peru and Brazil, ZooKeys 1188, pp. 27-45 : 27

Genus Trigava O'Brien, 1999

Trigava O’Brien, 1999: 60. Type species: Igava brachycephala Melichar, 1912; by original designation.

Diagnosis.

The genus may be distinguished by the following combination of characters: cephalic process conical, strongly curved upward, and gradually narrowing apicad; vertex with posterior plane elevated above pronotum, wider (e.g., at posterior margin) than transverse diameter of eyes in dorsal view, lateral carinae abruptly constricted and curved upward in front of eyes, converging anteriad, apical margin broadly angulately convex to nearly straight; frons flat, lateral, intermediate and median carinae weakly ridged, lateral carinae nearly parallel in most of their length, gradually converging apicad in front of eyes; pronotum with intermediate carinae ridged and nearly reaching posterior margin, upper lateral carina greenly thickened (not continued on the tegula), posterior margin angularly concave, not notched; mesonotum with lateral carinae incurved anteriad, reaching and connecting median carina; tegulae lacking carina; tegmina macropterous, veins setose on ventral surface, nodal line present, ScP+R+MP long, MP1+2, MP3+4 and CuA1 forked near nodal line (near midlength), the longest folding line between MP3 and MP4; fore femora without spines, hind tibiae with eight apical teeth; endosomal processes sclerotised apically; phallobase with pairs of large and stout spines.

Description.

General colour of body pale green to stramineous green, marked with green, ochraceous and black on head and thorax (Figs 1 , 2 ).

Head. Head (Figs 3A-C , 4A-C , 6A-C , 7A-C ) in front of eyes produced into a short cephalic process. Cephalic process conical, strongly curved upward, and gradually narrowing toward apex. Vertex (Figs 3A , 4A , 6A , 7A ) with posterior plane elevated above pronotum, wider than transverse diameter of eyes in dorsal view (Figs 3A , 4A , 6A , 7A ); lateral carinae keeled, gradually converging (with a lateral inflection anterior to eyes), abruptly constricted and curved upward in front of eyes, and then converging anteriad, in lateral view (Figs 3B , 4B , 6B , 7B ), the process bent upward at approximately 60-90° (sometimes more than 90°) in front of eyes; median carina indistinct, somewhat depressed medially, or weakly ridged posteriorly; apical margin broadly angularly convex to nearly straight, not acuminate at apex, posterior margin ridged and broadly and angularly concave, concavity projecting distinctly beyond middle of eyes. Frons (Figs 3C , 4C , 6C , 7C ) flat, elongate and relatively broad; lateral carinae weakly ridged, slightly expanded outward below antennae, nearly parallel in most of their length, gradually converging apicad in front of eyes; intermediate carinae weekly keeled, nearly reaching frontoclypeal suture; median carina complete but obscure. Frontoclypeal suture arched. Postclypeus and anteclypeus (Figs 3C , 4C , 6C , 7C ) cuneate, slightly convex medially; lateral and median carinae keeled. Rostrum long, second segment slightly longer than third segment, surpassing middle coxae, third segment reaching middle of hind femora. Compound eyes large and rounded, callus postocularis forming a triangular process protruded posteriad. Antenna with very small scape; pedicel subglobose, with more than 50 sensory plaque organs distributed over entire surface; flagellum long, setuliform.

Thorax. Pronotum (Figs 3A , 4A , 6A , 7A ) distinctly shorter than mesonotum medially, narrow anteriorly, broad posteriorly; anterior margin arcuately convex medially, lateral marginal areas convex and sloping with two long longitudinal carinae on each side between eyes and tegulae, upper lateral carina greenly thickened (not continued on the tegula); in dorsal view (Figs 3A , 4A , 6A , 7A ), lower lateral carinae expanded just behind eyes; posterior margin angularly concave, not notched; median carina distinct, with a deep lateral pit at side; intermediate carinae keeled and nearly complete. Mesonotum (Figs 3A , 4A , 6A , 7A ) distinctly tricarinate, lateral carinae incurved anteriad, reaching median carina. Tegulae lacking carina.

Tegmina (Figs 2G, H ) membranous, hyaline, and macropterous, extending far beyond the tip of abdomen; veins setose on ventral surface; transverse veinlets r-m, imp and mp-cu connecting some short segments of veins RP, MP and CuA to form nodal line; ScP+R+MP long, much longer than basal cell; ScP+R forked in distal 3/5; MP bifurcating MP1+2 and MP3+4 (forming cell C3) near midlength, MP1+2 and MP3+4 forked near level of bifurcation of ScP+R, near nodal line, MP1, MP2, MP3 and MP4 each forked at apex; CuA forked before bifurcation of MP (forming C5 cell), CuA1 bifurcating CuA1a and CuA1b before mp-cu, near nodal line; mp-cu connecting MP3+4 and CuA1a (forming C4 cell); Pcu and A1 fused in proximal third of clavus, composite vein reaching wing margin before claval apex (not reaching CuP); numbers of apical cells of RP, MP and CuA 3, 7, 3-4, respectively; pterostigmal area elongate, with three cells; folding lines present, the longest one between MP3 and MP4.

Hindwings with ScP+R+MP short, about a half of basal cell; ScP+RA and RP forked near apical one third; MP bifurcating MP1+2 and MP3+4 little posterior to ScP+RA and CuA; CuA bifurcating CuA1 and CuA2 much anterior to ScP+RA and MP, CuA1 four-branched distally, and CuA2 not branched; transverse veinlets r-m and mp-cu slightly posterior to bifurcation of MP.

Legs long; fore femora elongate, not flattened and dilated, without spines; fore and middle tarsomeres I and II with more than two acutellae; hind tibiae distinctly elongate, nearly twice as long as hind femora, with four lateral spines and eight apical teeth; hind tarsomeres I and II with about 7-9 and 8-9 apical teeth, respectively.

Male genitalia. Pygofer, in lateral view (Figs 3E , 4E , 6E , 7E ), irregularly quadrate to pentagonal, distinctly wider ventrally than dorsally, dorsal margin slightly excavated to accommodate segment X, dorsoposterior margins angular. Gonostyles (Figs 3F , 4F , 6F , 7F ) symmetrical, in lateral view (Figs 3G , 4G , 6G , 7G ) broad, base narrow, expanded distally, broadest in middle, and then tapering posteriad, apex rounded; dorsal margin with a claw-like, apically sclerotised process (dorsal process), directed dorsad, outer dorsal edge with a hook-like process near middle, directed ventrad. Aedeagus (Figs 3H-J , 4H-J , 6H-J , 7H-J ) with a pair of endosomal processes extended from phallotheca and curved dorsoanteriad or laterad; these processes mostly membranous, sclerotised apically, tapering posteriad to form large and stout spines; phallobase sclerotised basally and membranous and inflated apically, with paired lobes with large and stout spines. Segment X long oval, in lateral view (Figs 3E , 4E , 6E , 7E ), ventral margin gradually widening from base to apex; in dorsal view (Figs 3D , 4D , 6D , 7D ), with apex excavated to accommodate anal style; anal style elongate and large, beyond apical ventral margin of segment X.

Female genitalia. Gonocoxae VIII (Fig. 5D ) with a membranous and flattened endogonocoxal processes (Gxp), bearing tiny setae on apex. Gonapophyses VIII (Fig. 5D ) with anterior connective lamina large and sclerotized, with seven teeth of varying sizes and shapes. Gonapophyses IX (Fig. 5E, F ) with posterior connective lamina triangular, symmetrical, weakly bifurcated at apex, fused with the intergonocoxal plate at base. Gonoplacs (Fig. 5G, H ) with two lobes homologous, first lobe (lateral lobe) axe-shaped, sclerotized, large and elongate, apical margin filmy and truncate, with cluster of long setae on apex (no sensory appendage, viz. Igava spp.); second lobe (posterior lobe) large, broad basally and tapering posteriad, the edge membranous containing long sclerotized plate. Segment X (Fig. 5A ) trapeziform, large and broad in dorsal view, apex deeply excavated to accommodate anal style; anal style small.

Diversity and distribution.

Trigava is revised here to contain four species including two new species. The species of the genus are distributed in the northwest of South America and were recorded from Peru, Bolivia and Brazil, as far as known (Fig. 8 ).

Remarks.

In addition to the diagnostic characters listed by O’Brien (1999), Trigava may be separated from Igava Melichar by characters diagnostic at the tribal level, such as on the tegmen and the female genitalia ( Song et al. 2018). For example, the second postnodal line of the tegmen and the apical sensory appendage of gonoplacs I are absent in Trigava , but they are present in Igava .

In the tribe Nersiini , Trigava is externally similar to the genus Nersia Stål, 1862, but can be distinguished from the latter by the head strongly curved upward (slightly curved upward in Nersia ); the median carina of vertex absent (present in Nersia ), and the tegulae lacking carina (present in Nersia ). See also the Discussion.

Figures

Figure 1. Habitus of Trigava species, dorsal view A T. brachycephala (Melichar), lectotype, male B T. brachycephala (Melichar), male C T. obrieni sp. nov., holotype, male D T. obrieni sp. nov., paratype, female E T. peruensis sp. nov., holotype, male F T. recurva (Melichar), lectotype, male.

Figure 2. Habitus of Trigava species, lateral view A T. brachycephala (Melichar), lectotype, male B T. brachycephala (Melichar), male C T. obrieni sp. nov., holotype, male D T. obrieni sp. nov., paratype, female E T. peruensis sp. nov., holotype, male F T. recurva (Melichar), lectotype, male G right tegmen of T. brachycephala H right tegmen of T. recurva.

Figure 3. Trigava brachycephala (Melichar), male A head and thorax, dorsal view B same, lateral view C same, ventral view D pygofer and segment X, dorsal view E pygofer, gonostyles, aedeagus and segment X, right lateral view F pygofer and gonostyles, ventral view G left gonostyle, lateral view H aedeagus, dorsal view I aedeagus, lateral view J aedeagus, ventral view.

Figure 4. Trigava obrieni sp. nov., holotype, male A head and thorax, dorsal view B same, lateral view C same, ventral view D pygofer and segment X, dorsal view E pygofer, gonostyles, aedeagus and segment X, right lateral view F pygofer and gonostyles, ventral view G left gonostyle, lateral view H aedeagus, dorsal view I aedeagus, lateral view J aedeagus, ventral view. Abbreviations: as, anal style; dl, dorsal lobes of phallotheca; dmp, dorsal margin of pygofer; dpg, dorsal process of gonostyle; ep, endosomal processes; gs, gonostyle; hpg, hook-like process of gonostyle; ll, lateral lobes of phallotheca; pg, pygofer; pt, phallotheca; sx, segment X; vl, ventral lobes of phallotheca; vmp, ventral margin of pygofer.

Figure 5. Trigava obrieni sp. nov., paratype, female A terminalia, dorsal view B same, lateral view C same, ventral view D gonapophysis VIII, lateral view E gonapophysis IX, ventral view F gonapophysis IX, lateral view G gonoplac, lateral view H gonoplac, dorsal view. Abbreviations: ACL, anterior connective lamina of gonapophysis VIII; Gp I, first lobe (lateral lobe) of gonoplac; Gp II, second lobe (posterior lobe) of gonoplac; GxL, endogonocoxal lobe; GxP, endogonocoxal process; Gx VIII, gonocoxae VIII; PCL, posterior connective lamina; sx, segment X.

Figure 6. Trigava peruensis sp. nov., holotype, male A head and thorax, dorsal view B same, lateral view C same, ventral view D pygofer and segment X, dorsal view E pygofer, gonostyles, aedeagus and segment X, right lateral view F pygofer and gonostyles, ventral view G left gonostyle, lateral view H aedeagus, dorsal view I aedeagus, lateral view J aedeagus, ventral view.

Figure 7. Trigava recurva (Melichar), lectotype, male A head and thorax, dorsal view B same, lateral view C same, ventral view D pygofer, and segment X, dorsal view E pygofer, gonostyles, aedeagus and segment X, right lateral view F pygofer and gonostyles, ventral view G left gonostyle, lateral view H aedeagus, dorsal view I aedeagus, lateral view J aedeagus, ventral view.

Figure 8. Geographical distribution of Trigava species.