Concavetettix Deng, 2021

Lu, Xiang-Yi & Deng, Wei-An, 2021, New genus and new species of the subfamilyMetrodorinae from China (Orthoptera Tetrigidae), Zootaxa 4964 (2), pp. 345-362 : 347

Genus Concavetettix Deng , gen. nov.

Type species: Concavetettix yunnanensis Deng , sp. nov., here designated.

Description. General characters and coloration. Size small. Colouration uniformly dark brown. Body interspersed with coarse protuberances and concavities.

Head. Head and eyes exserted above pronotal surface. Vertex obviously concave, width of vertex between eyes wider than width of compound eye; anterior margin of fastigium nearly truncate, not surpassing anterior margin of eye; transverse carina of vertex directed upwards and elevated the same level of upper margin of compound eye. In lateral view, frontal ridge invisible between eyes, protruded anteriorly and broadly rounded between antennal grooves. In frontal view, vertex depressed and with U-shaped concavity; width of longitudinal furrow of frontal ridge distinctly narrower than antennal groove diameter. Antennae filiform, 15-segmented, antennal grooves inserted below inferior margin of compound eyes. Eyes globose, lateral (paired) ocelli located lowest third of compound eye height.

Thorax. Pronotum platy, in dorsal view, dorsum of pronotum with irregular concavities and coarse tubercles, with a straight anterior margin, with a distinct obtuse projecting under each lateral carina of prozona; median carina interrupted. In profile, upper margin of pronotum near the anterior margin concaved, arch-like before shoulders and straight behind shoulders; humeral angle obtuse; hind pronotal process narrow, reaching apex of hind femur and its apex narrowly rounded. Posterior angles of lateral lobes produced outwards, end of posterior angles truncate, posterior margins of lateral lobes of pronotum only with ventral sinus. Tegmina and hind wings absent.

Legs. Fore and middle femora compressed, ventral margins each with one to two small projections and undulated; width of fore femora equal to the width of middle femora. Hind femora robust and short, margins finely serrated, with one to two tubercules on outside behind the middle; antegenicular denticles and genicular denticles acute. The first segment of posterior tarsi and the third equal in length.

Diagnosis. New genus is allied to Platythorus Morse, 1900 , but differs by follows: head and eyes exserted above pronotal surface (not exserted in Platythorus ); vertex obviously concave (not concave in Platythorus ); with a distinct obtuse projecting under each lateral carina of prozona (without obtuse projecting in Platythorus ); dorsum of pronotum with irregular concavities and coarse tubercles(dorsum of pronotum smooth in Platythorus ). New genus is similar to Macromotettixoides Zheng, Wei & Jiang, 2005 , but differs by follows: head and eyes exserted above pronotal surface (not exserted in Macromotettixoides ); vertex obviously concave (not concave in Macromotettixoides ); with a distinct obtuse projecting under each lateral carina of prozona (without obtuse projecting in Macromotettixoides ); hind femora with one to two tubercules on outside behind the middle (smooth and without tubercule in Macromotettixoides ); pronotum platy, dorsum with irregular concavities and coarse tubercles (pronotum tectiform, generally without concavity in Macromotettixoides ).

Etymology. The generic epithet is derived from “ Concave ”, meaning dorsum of pronotum with irregular concavities.