A new genus, Smilirhexia, of Smiliini (Hemiptera, Membracidae) from Costa Rica Author McKamey, Stuart USDA Agricultural Research Service, Systematic Entomology Laboratory, Washington, United States of America text ZooKeys 2008 2008-09-16 3 3 51 55 journal article 10.3897/zookeys.3.29 68f2e86e-3760-4c9e-bff2-47baad473bee 1313–2970 576417 45774FDF-CF37-4A92-A63F-8A0BFC15B5A9 Smilirhexia McKamey , gen. n. urn:lsid:zoobank.org:act: AD148098-EBFC-46EA-BF5D-B74F697FD853 Type species: Smilirhexia naranja , sp. n. Diagnosis . The new genus differs from all other genera of the tribe in having a smooth and shining pronotum, which is broad, almost completely convex, and brightly colored. Description of male. Head ( Fig. 3 ) glabrous, subtriangular in anterior view, ocelli equidistant from each other and from eyes. Pronotum ( Figs 1-3 ) entirely concealing scutellum, convex, dorsal carina elevated only in posterior half, and weakly, otherwise delineated by absence of punctures; surface shining, punctures shallow and lacking setae; humeral angles not projected laterally beyond wing bases; posterior pronotal process ending at apex of forewing cell M 3+4 (last apical cell). Forewing ( Fig. 1 ) free, in repose not concealed wholly or in part by pronotum; without r-m crossveins, with veins R and M adjacent basally, weakly divergent soon after, R 4+5 and M 1+2 confluent for a short distance before apex, and strongly divergent at wing apex; R 2+3 present as distinct branch of R; R 4 and R 5 separately joined to vein M, creating a small cell R 4 near center of wing. Hind wing with short r-m crossvein ( holotype right wing) or veins R and M fused at single point ( holotype left wing). Femora, tibiae, and tarsomeres lacking cucullate setae except metathoracic femur with two apically, metathoracic tibia with three rows (row 2 double), and metathoracic tarsomere I with 4 cucullate setae at apex. Metathoracic coxa and trochanter without apposed processes. Abdomen lacking fenestrae or mid-dorsal protuberances. Female . Unknown. Distribution . Costa Rica , Puntarenas Prov. Material Examined. Holotype male of Smilirhexia naranja , sp. n. Etymology . The new genus name is feminine and combines the name of its apparent tribe and the name of an unrelated genus, Rhexia Stål , which it resembles superficially [e.g., Rhexia viridicollis (Fowler) , illustrated by Deitz (1983) ]. Discussion . The distally confluent radial and medial veins, which diverge before the forewing apex, and the lack of processes on the metathoracic coxa and trochanter place the new genus firmly in the subfamily Smiliinae . In Deitz’s key to the higher classification, the genus keys to the tribe Smiliini due to the presence of 2 m-cu crossveins. The only discrepancy is that in the new genus, the forewing is completely exposed rather than partially concealed. Most genera of the tribe are morphologically similar and authentic records of only a few species exist for Central America, the tribe’s southern limit. The notable exception is the genus Antianthe Fowler , which is laterally compressed, strongly crested, and with pronounced humeral angles, and which occurs from the southern USA to South America. Smilirhexia appears to represent another distinct morphological form for Smiliini that may help to elucidate the evolutionary origin of this tribe. Species of the subfamily Darninae , which appears to be a close relative of Smiliinae , also have the forewing with two r-m crossveins, as in Smiliini . Interestingly, Cymbomorpha Stål (Cymbomorphini, Darninae ) occasionally have the characteristic forewing venation of Smiliinae , with veins R and M confluent for a short distance before the apex, and double setation in metathoracic tibial row II. Both Cymbomorpha and Eumela Stål , the other cymbomorphine genus, and Smilidarnis Andrade, 1989 (a Neotropical, unplaced genus with characters of both Darninae – especially Cymbomorphini – and Smiliinae ), exhibit the shining pronotal surface and completely exposed forewings of the new genus Smilirhexia .