Gibbocicada, Ruschel, 2018

Ruschel, Tatiana Petersen, 2018, Gibbocicada brasiliana, new genus and new species from Brazil and a key for the genera of Tibicinini (Hemiptera: Auchenorrhyncha: Cicadidae), Acta Entomologica Musei Nationalis Pragae 58 (2), pp. 559-566 : 561

Gibbocicada gen. nov.

( Figs 2–18 )

Type species. Gibbocicada brasiliana sp. nov., here designated.

Diagnosis. The new genus can be distinguished from all other genera in the Tibicinini by the following combination of characters: head short, three times shorter than pronotoum in dorsal view ( Fig. 6 ); lateral ocelli almost reaching the anterior margin of pronotum in dorsal view ( Fig. 6 ); anterior margin of lateral lobe of pronotum reaching the eyes ( Fig. 6 ); pronotum and mesonotum pronounced dorsally in lateral view ( Fig. 5 ); dorsal midline of pronotal collar very broad, as wide as the diameter of eye ( Fig. 6 ); lateral angle of pronotal collar laterally pronounced ( Fig. 6 ); meracanthus large, of the same length as operculum ( Fig. 9 ); fore wings with the median and cubitus anterior veins rising from the same point in the basal cell ( Fig. 3 ); tergite 1 fully covered by cruciform elevation; uncus posteriorly developed ( Fig. 13 ); basal lobe long, almostreaching the uncus ( Fig. 13 ). The new genus can be distinguished from Okanagodes by the distance between the lateral ocellus and eyes greater than diameter of ocellus, and by the postclypeus short, slightly prominent relative to the anterior margin of head in dorsal view; from Clidophleps by the medial cell notmuch narrower than radial cell; from Okanagana by the head (including eyes) broader than the pronotum; from Paharia , Subpsaltria , and Tibicina by the pronotum long, three timeslonger than head, the aedeagus not elongated nor curved anteriorly; from Subtibicina by the fore wings being broad (less than three times the length), not tinged with yellowish brown, and by the uncus being arched and not flat; and from Tibicinoides by the base of wings colorless, and the medial cell of fore wings almost twice longer than ulnar cell 3.

Description. Head ( Fig. 6 ) (including eyes) wide, slightly broader than pronotum (excluding the pronotal collar), and narrower than mesonotum; head short, three times shorter than pronotoum in dorsal view. Lateral ocelli widelyseparated and almost reaching the anteriormargin of pronotum. Vertex wide, the distance between the lateral ocellus and eyes greater than diameter of ocellus. Supra-antennal plates not prominent and not meeting eye. Postclypeus short and narrow in dorsal view, its width equal to the distance between the lateral ocelli; slightly prominent relative to the anterior margin of head in dorsal view; rectangular in ventral view ( Fig. 7 ) and obtuse in lateral view. Pronotum and mesonotum pronounced dorsally in lateral view ( Fig. 5 ). Pronotum ( Fig. 6 ) long, three times longer than head, not depressed laterally; anterior margin of lateral lobe of pronotum reaching the eyes; pronotal collar broad in dorsal view, as wide as diameter of eye; lateral angle of pronotal collar laterally pronounced, exceeding the lateral margin of mesonotum; lateralpart of pronotalcollar narrow relative to lateral angle. Mesonotal stridulatory apparatus absent. Operculum ( Fig. 9 ) broad, the lateral andposterior margins slightly convex, and distal margins not reaching thedistal margins of tympanal cavities. Meracanthus ( Fig. 9 ) large, of the same length as operculum. Basisternum 3 flat, covered by the meso- and metacoxae. Cruciform elevation with the central and lateral areas flat. Profemora armed with two spines, the primary one the longest and parallel to the posterior margin of femur, and the secondary one sharp and straight. Tarsi three-segmented. Fore wings ( Fig. 2 ) hyaline; broad, width almost three times the length; with eight apical cells; the median and cubitus anterior veins rising from the same point in the basal cell; medial cell almost twice longer than ulnar cell 3 and not much narrower than radial cell; hind wings ( Fig. 2 ) about half the length of fore wings, with six apical cells. Male timbal covers absent ( Fig. 10 ). Tergite 1 fully covered by cruciform elevation. Sternite II ( Fig. 8 ) distant from metacoxae. Uncus longer than sternite VIII, elevated and posteriorly developed. Basal lobe of pygofer long, almost reaching the uncus ( Fig. 13 ). Aedeagus not elongated nor curved anteriorly ( Fig. 12 ).

Etymology. The name is derived from the Latin adjective gibbus (= humped) and the noun cicada (= cicada). Itrefers to the pronotum and mesonotum which are both pronounced dorsally in lateral view. The gendre is feminine.

Comments. Based on the diagnosis of the subfamily proposed by MARSHALL et al. (2018), Gibbocicada gen. nov. clearly belongs to the Tibicininae by the metanotum concealed at dorsal midline ( Fig. 2 ); the hind wing veins RP and Munfused at their bases ( Figs 3, 4 ); the distal marginsof male operculum not reachingthe distal margins of tympanal cavities and basallynot extendingbeyond meracanthus, but notin S-shape ( Fig. 9 ); males lackingtimbal covers ( Fig. 10 ); pygofer distal shoulder undeveloped; pygofer upper lobe absent; uncus very long and not retractable within pygofer; claspers absent; and the presence of a ventrobasalpocket ( Figs 12–14 ). The forewing veins CuP and 1A are unfused in most genera of Tibicininae , but fused in Platypedia Uhler, 1888 and Neoplatypedia Davis, 1920 (Platypediini) ( MARSHALLet al. 2018). Gibbocicada gen. nov. presents these veins partially fused, i.e. thebasal third of CuP and 1A are unfused ( Fig. 3 ).

Among all tribes of Tibicininae , Gibbocicada gen. nov. is more similar to the genera classified in Tibicinini , with the pronotum more or less distinctly narrowed anteriorly ( Fig. 6 ); fore wings talc-like and obscurely wrinkled, their greatest breadth more than one third of their length ( Fig. 2 ); abdomen subcylindrical ( Fig. 2 ); and uncus longer than sternite VIII ( DISTANT 1905). LEE (2012) listed other characteristics shared by the genera of Tibicinini that Ialso observed in Gibbocicada gen. nov.: hind wing first cubital cell width at distal end about equal to second cubital cell; male operculum not reaching posterior margins of sternite II ( Fig. 9 ); pygofer upper lobes absent, claspers absent and uncus very long ( Figs 13, 14 ). The new genus cannot be placed in the other tribes of Tibicininae for the lack of their diagnostic characters, i.e. Tettigadini because the species in the tribe are characterized by the lateral margins of the pronotum dilated and usually medially angulate ( DISTANT 1905), and by a mesonotal stridulatory apparatus ( JACOBI 1907, BOULARD 1976, MOULDS 2005); Selymbrini because they have supra-antennal plates almostreaching the eye, a rounded postclypeus, hind coxae without lateral protruberance and a very short theca laterally expanded and distally ornamented ( MARSHALL et al. 2018); Chilecicadini Sanborn, 2014 because they havethe anteriorpronotum about as wide as the posterior pronotum, the lateral angle of the pronotal collar anteriorto thehind margin, and the partiallyexcavated lateral margin of the pronotal collar ( SANBORN 2014); and Platypediini Kato, 1932 because the tribe includes only species without timbal organs ( MOULDS 2005).

Figures

Figs 2–11. Gibbocicada brasiliana gen. et sp. nov., holotype, male. 2 – habitus in dorsal view; 3 – wings in dorsal view (arrow points to the basal third of CuP and 1A which are unfused); 4 – detail of hind wing veins in dorsal view (arrow points to veins RP and M which are unfused at their bases); 5 – habitus in lateral view (wings not extended); 6 – head and pronotum in dorsal view; 7 – postclypeus in ventral view; 8 – thorax in ventral view; 9 – operculum in latero-ventral view; 10 – timbal in latero-ventral view; 11 – sternites VII and VIII in ventral view.Abbreviations: 1A – anal vein, CuA – cubitus anterior vein, CuP – cubitus posterior vein, M – median vein, mc – meracanthus, op – operculum, RP – radius posterior vein, tim – timbal, tymc – tympanal cavity, st – sternite. Scale bars: 2 – 2 cm; 3, 5 – 5 mm; 6–8, 11 – 2 mm; 4, 9, 10 –1 mm.

Figs 12–14. Gibbocicada brasiliana gen. et sp. nov., paratype, male. 12 – Pygofer, uncus and aedeagus, in latero-ventral view; 13 – same, in lateral view; 14 – aedeagus in ventral view. Abbreviations: aed – aedeagus, as – anal styles, at – anal tube, bl – basal lobe, pyg – pygofer, un – uncus, vb – ventral branches, ve – vesica, vbp – ventrobasal pocket. Scale bars: 12, 13 – 1 mm; 14 – 0.5 mm.

Figs 15–18. Gibbocicada brasiliana gen. et sp. nov., paratype, female. 15 – habitus in dorsal view; 16 – operculum in latero-ventral view; 17 – sternite VII, abdominal segment 9 and ovipositor sheath in ventral view; 18 – tergites 5–9 in lateral view.Abbreviations: ab9 – abdominal segment 9, db – dorsal beak, mc – meracanthus, op – operculum, os – ovipositor sheath, st – sternite. Scale bars: 15 – 2 cm; 16 – 1 mm; 17, 18 – 2 mm.