A new species of Oecleus (Hemiptera: Auchenorrhyncha: Fulgoromorpha: Cixiidae) from the Osa Peninsula in Costa Rica Author Zumbado Echavarria, Marco A. 0000-0002-2591-7662 Universidad of Costa Rica - Sede San Ramón, Departmento de Ciencias Naturales, de la Iglesia el Tremedal 400 mts al Oeste carretera hacia San Pedro, San Ramón, Alajuela, Costa Rica. & marco. zumbado @ ucr. ac. cr, nassua 75 @ gmail. com; https: // orcid. org / 0000 - 0002 - 2591 - 7662 nassua75@gmail.com Author Barrantes Barrantes, Edwin A. 0000-0001-9565-2105 Universidad of Costa Rica - Sede San Ramón, Departmento de Ciencias Naturales, de la Iglesia el Tremedal 400 mts al Oeste carretera hacia San Pedro, San Ramón, Alajuela, Costa Rica. & edwin. barrantes @ ucr. ac. cr, edwbarrantes @ gmail. com; https: // orcid. org / 0000 - 0001 - 9565 - 2105 edwbarrantes@gmail.com Author Bartlett, Charles R. 0000-0001-9428-7337 University of Delaware, Department of Entomology and Wildlife Ecology, 250 Townsend Hall, Newark, DE 19716 - 2160, USA. bartlett @ udel. edu; https: // orcid. org / 0000 - 0001 - 9428 - 7337 bartlett@udel.edu Author Helmick, Ericka E. 0000-0002-5153-0891 University of Florida, Department of Entomology and Nematology - Fort Lauderdale Research and Education Center; 3205 College Ave., Davie, FL 33314 - 7719, USA. & ehelmick @ ufl. edu; https: // orcid. org / 0000 - 0002 - 5153 - 0891 ehelmick@ufl.edu Author Bahder, Brian W. 0000-0002-1118-4832 University of Florida, Department of Entomology and Nematology - Fort Lauderdale Research and Education Center; 3205 College Ave., Davie, FL 33314 - 7719, USA. & bbahder @ ufl. edu; https: // orcid. org / 0000 - 0002 - 1118 - 4832 bbahder@ufl.edu text Zootaxa 2023 2023-09-04 5339 6 533 546 http://dx.doi.org/10.11646/zootaxa.5339.6.3 journal article 10.11646/zootaxa.5339.6.3 1175-5326 8313741 BAB980D6-C504-4E78-B1B9-640020C5CCD3 Genus Oecleus Stål, 1862 Type species: Oecleus seminiger Stål, 1862: 306 . Diagnostic features. (Modified after Kramer 1977 and Barrantes et al . 2022 ) Small to midsize ( 3.3–8.5 mm ; usually 3.5–6.0); head and eyes narrower than pronotum in dorsal view. Head appearing rounded to slightly projected from lateral view. Vertex narrow, trough-like and parallel-sided, distal margin with transverse carina, sides carinate and raised; proximally narrowed and distally produced beyond eyes for a variable distance. In lateral view, apex of head acutely or obtusely angled, eyes large, emarginate near antennae, lateral ocelli present just under each eye (just anterior to antennae) and median ocellus near midline above frontoclypeal suture. In frontal view, frons elongately ovate, lateral margins arched (widest below eye) and narrowing towards vertex, carina on midline of frons present (sometimes obsolete). Clypeus triangular to subtriangular (median carina present). Antennae originating from a large socket, scape small, collar-like, pedicel globular with sensoria, flagellum beadlike basally and filamentous distally. Pronotum short with irregular ridges, narrowest on midline, indented on posterior margin, carinate on posterior and lateral margins. Mesonotum longer at midline than vertex and pronotum combined, flattened, usually with five longitudinal carinae; intermediate carinae sometimes reduced to pigmented lines. Hind tibiae lacking lateral spines. Forewings transparent, rarely with patterns, veins usually dotted with pustules, often bearing setae; composite vein ScP+ R + MP elongate from basal cell. Pygofer broadly triangular in lateral view (narrowed dorsally, broadly enlarged ventrally); in ventral view bearing medioventral lobe (often situated on quadrangular plate). Gonostyli simple (usually with large median dentation subapically). Aedeagus with shaft straight (or nearly so), usually bearing 1–3 processes (1–2 subapical), endosoma retrorse, membranous, usually bearing 1–3 processes. Anal tube large and elongate, varied in form.