Kaikaia, Morris & Dietrich, 2020

Morris, Brendan O. & Dietrich, Christopher H., 2020, An unusual new genus and species of centrotine treehopper (Hemiptera: Membracidae: Centrotinae) from Nicaragua, Zootaxa 4729 (2), pp. 286-292 : 287-290

Kaikaia new genus

( Figs 1 , 2 )

Type species. Kaikaia gaga Morris & Dietrich

Diagnosis. This genus may be readily distinguished from other Centrotinae by the following combination of features: Pronotum with suprahumeral horns well developed, tapered; posterior process appressed against scutellum; scutellum well exposed laterally; forewing with two m-cu crossveins (m-cu 2 sensu Wallace & Deitz 2004 absent); mesothoracic tibia and femur without cucullate setae; metathoracic femur without scattered supernumerary dorsal cucullate setae apically, apical ablateral and preapical adlateral cucullate setae present; ventrolateral margin of abdominal tergite III shelf-like; female second valvulae slender, with acute projection and few prominent preapical teeth; anterior abdominal tergites without paired dorsal swellings, but with very slight medial depression.

Description. Medium sized (9.3 mm long). Coloration. Reddish brown to dark castaneous Structure. Head with vertex slightly more than twice as wide as long, with very weak dorsomedial concavity; faint median carina present; ventral lobes mostly straight, weakly produced below ventral margin of eye, slightly upturned. Ocelli approximately equidistant from each other and corresponding eye (slightly closer to midline than to corresponding eye), approximately even with dorsal margin of eyes. Frontoclypeus flat, not depressed with respect to ventral lobes of vertex, slightly projecting ventrad in profile, without median longitudinal carina, margins parallel and abruptly broadened apically with ventral margin slightly upturned; frontoclypeal lobes moderately developed, distinct, extended slightly beyond ventral lobes of vertex, nearly reaching but not surpassing mid-length of frontoclypeus. Rostrum extending to base of mesocoxae. Pronotum densely punctate, finely pilose, each pit bearing single whitish-silver recumbent seta. Supraocular callosities concolorous. Suprahumeral horns present, stout basally, extended dorsolaterally at approximate 45 degree angle, apices acute, anterior edge slightly curving posteriorly, carinae absent on dorsal and ventral surfaces. Posterior process straight, appressed against and covering scutellum dorsally but only partially concealing scutellum laterally; slender, slightly broadened medially then gradually tapered to apex, extending beyond base of 2 nd m-cu crossvein (m-cu 3 sensu Wallace & Deitz, 2004) but not surpassing apex of forewing; dorsal midline carinate, single longitudinal carina present laterally above and posterior to scutellum, ventral carinae present, venter strongly convex preapically. Scutellum emarginate, exposed posterolateral lobes punctate and finely pilose, apices acute, nearly entire notch visible in ventral view (with the abdomen removed). Forewing with opaque punctate sclerotization restricted to small areas adjacent to base of costal margin and base of clavus; pterostigma absent; crossvein r-m1 extended obliquely from just basad of m-cu 1 to point just distad of fork of R 2+3 and R 4+5; R 1 moderately long, forming more or less continuous line with stem of R; base of cell formed by R 2+3 and R 4+5 truncate; R 4+5 slightly angled proximal to crossvein s; crossvein r-m 2 approximately equidistant between crossvein s and base of R 2+3 and R 4+5; M and Cu not fused, but closely adjacent at base; proximal and distal m-cu crossveins (m-cu 1 and m-cu 3) present; R, M, and Cu veins not parallel apically. Hind wing with R 4+5 and M 1+2 not fused, connected by crossvein (4 apical cells) ( Fig. 1 D ). Pro- and mesothoracic legs without cucullate setae, tibiae slender. Metathoracic femur with ablateral and adlateral cucullate seta present near apex; tibia with three well developed rows of cucullate setae, setal row II present as irregular double row; apex of tarsal segment I with two cucullate setae ventrally. Anterior abdominal tergites without clear remnants of paired dorsomedial swellings, but with slight medial depression possibly indicating presence of very slight swellings, anterior margins modified into irregular ridges, tergum III ventrolaterally thickened and forming shelf-like structure; sternites without carinae; pits present. Female second valvulae narrow, nearly straight, with several distinct, rounded teeth present preapically, one basal acute projection, apex slightly acuminate, very weakly serrated; third valvulae with apical cleft ( Fig. 2C ).

Notes: This genus resembles New World centrotine tribes Platycentrini and those Nessorhinini near Orthobelu s Stål in features of the forewing (1 m-cu crossvein proximally in addition to m-cu3) in having hind wing veins R 4+5 and M 1+2 separate, joined by m-cu crossvein (4 apical cells present) and abdominal terga with anterior borders modified into irregular ridges; but may be readily distinguished by the features mentioned in the Diagnosis. Remarkably, this genus strongly resembles the Old World distributed Beaufortianini in overall appearance, and more specifically in having the lateral lobes of the frontoclypeus distinct with frontoclypeal margins broadening apically (similar to Centruchus Stål and Centrotusoides Distant ). Nevertheless, the shape and structure of the female second and third valvulae strongly resemble those of some members of the Caribbean endemic tribe Nessorhinini, which, like the new genus, have tergite III forming a shelf-like process laterally. In other regards the genus resembles Platycentrini, particularly in characters of the forewing: R 1 vein long, running approximately parallel to the marginal vein, (only weakly bent towards marginal vein in Platycentrus ), r-m 2 equidistant between s and base of R 2+3 and R 4+5, and two m-cu crossveins present. Kaikaia differs from Platycentrini and Boocerini in features of the female genitalia, i.e., 2 nd valvulae narrow with large, prominently raised teeth (also present in Nessorhinini; Dietz 1975) and in lacking cucullate setae on the mesothoracic leg. Moreover, a full apical notch of the scutellum is visible in ventral view (with the abdomen removed), which is characteristic of Monobelini and Boocerini (also some Gargarini ). Like some Boocerini, Nessorhinini and Monobelini, the genus lacks cucullate setae on the mesothoracic femur. Kaikaia is similar to other New World centrotines in having hind wing veins R 4+5 and M 1+2 separate and connected by a crossvein (4 apical cells present) and abdominal terga with anterior borders modified into irregular ridges, but may be readily distinguished by the following combination of features: forewing with 2 m-cu crossveins (m-cu 1 and m-cu 3 present sensu Wallace & Deitz 2004), mesothoracic tibia and femur without cucullate setae, metathoracic femur without extra dorsal cucullate setae; ventrolateral margin of abdominal tergite III shelf-like; female second valvulae narrow, with numerous prominently raised teeth preapically; 3rd valvulae with preapical cleft; no obvious remnants of paired dorsal swellings present on anterior abdominal tergites (slight medial depression). Given the unusual combination of morphological features, suggesting mixed affinities to several centrotine tribes, the new genus is here considered unplaced to tribe within Centrotinae .

Distribution. Nicaragua.

Etymology. The genus name is derived from the Miskito infinitive conjugation of the verb “kaikaia” meaning “to see” and is treated as a feminine noun.

Figures

FIGURE 1. Habitus, hind wing.A) Kaikaia gaga holotype female (BOM_10000130), lateral habitus view. B) K. gaga holotype female (BOM_10000130), anterior habitus view. C) K. gaga holotype female (BOM_10000130), dorsal habitus view. D) K. gaga holotype female (BOM_10000130), hind wing.

FIGURE 2. Female valvulae.A) Kaikaia gaga holotype female (BOM_10000130), second valvulae apex. B) K. gaga holotype female (BOM_10000130), second valvulae. C) K. gaga holotype female (BOM_10000130), third valvulae.