Diablophthalmus, Dietrich, 2022

Dietrich, Christopher H., 2022, A New genus of flightless leafhoppers (Hemiptera: Cicadellidae: Megophthalminae) from the Páramo of Northern South America, Zootaxa 5141 (3), pp. 270-276 : 271-274

Diablophthalmus new genus

( Figures 1–3 )

Type species: D. wygodzinskyorum , sp. n., here designated.

Diagnosis. This genus is easily distinguished from other Megophthalmini by the pair of anteriorly projecting horns arising from the dorsal part of the head, by the vestigial ocelli and by the elliptical, elytralike forewings.

Description. Small beetlelike leafhoppers. Overall color brown with obscure paler markings. Body surfaces finely granulose, clothed with fine pale setae, some setae on head and legs with elevated bases (chalazae). Head with crown in dorsal view concave and very short medially, with pair of large conical lateral projections extended anterad. Eyes large and bulbous. Face concave dorsomedially, frontal sutures represented by variably developed carina extended from midheight of antennal ledge mesad, ocelli vestigial, represented by small unpigmented areas ventromesad of dorsal projections and just dorsomesad of antennal ledges. Frontoclypeus convex medially, concave adjacent to antennal ledge; antennal ledge prominent, nearly vertical, margin strongly curved; antenna as long as width of head between eyes, basal part of flagellum enlarged and forming distinct subsegment. Gena angulately emarginate below eye, broadened ventrally and completely concealing proepisternum; border of gena and maxillary plate indicated by weak carina. Lorum narrow, half bordering anteclypeus and half bordering frontoclypeus, convex dorsally and ventrally with concavity at midlength. Anteclypeus elliptical, extended well beyond ventral margin of maxillary plate. Rostrum slender, tapered, extended to hind coxae.

Pronotum short, with pair of lateral submarginal depressions, lateral margin subequal in length to eye in lateral view, weakly carinate, carina even with posterior corner of eye, ventrolateral lobe expanded and concealing dorsal part of episternum. Mesonotum depressed posterad of pronotum; scutellum strongly convex and transversely rugose. Forewing elliptical and convex, elytralike, venation not elevated, obscure over most of wing, with supernumerary branches reaching apical margin; costal margin strongly bicarinate throughout length, broad at base, tapered distally; clavus not well differentiated from corium, with elongated gibbosity near base of junction between wing sections. Hind wing vestigial, reduced to small pad extended only slightly posterad of metathorax in both sexes. Front and middle femora and tibiae clothed with numerous undifferentiated setae, tibiae cylindrical. Hind femur with two apical macrosetae and several smaller setae preapically; tibia PD: AD: AV: PV setae approximately 8:10:6:6 with numerous additional setae only slightly smaller than macrosetae scattered over surface; tarsomere I with pecten undifferentiated.

Male abdomen without dorsal tubercles; 2S apodemes weakly developed. Pygofer with dorsum well sclerotized but short, posterodorsal margin with sclerotized band but processes absent, groups of fine setae present ventrolaterally, along posterodorsal margin and near apex of lobe, lobe with weak oblique unsclerotized cleft preapically. Valve broadly fused to pygofer. Subgenital plates partially fused to valve and to each other at base, depressed and tapered distally, with scattered short, fine setae. Style robust, cheliform with preapical lobe as long as apophysis. Connective bandlike, oriented vertically and strongly sinuate in lateral view. Aedeagus U-shaped in lateral view, shaft abruptly expanded distally with apex rounded; dorsal apodeme T-shaped in posterior view; gonopore at apex of shaft on dorsal surface. Anal tube (segment X) simple, moderately long, well sclerotized dorsally and laterally, without processes or sclerotized basal collar, posteroventral lobe developed but weakly sclerotized.

Female with pregenital abdominal segments as in male. Sternite VII longer than sternite VI, with posterior margin bilobed. First valvula moderately long and slender, evenly tapered to sharp point distally, dorsal sculpturing reticulate with cells ovoid and arranged in more or less distinct rows extended obliquely distad from midheight of valvula to dorsal margin, apically merging with short ventral sculptured area of similar texture. Second valvula slightly broadened from base to about distal fifth, then with dorsal margin evenly declined to bluntly pointed apex, with distinct dorsal unsclerotized area near midlength, distal part of dorsal margin finely and somewhat irregularly serrate. Gonoplac with irregular ventral row of short setae.

Etymology. The name, which is masculine, was formed by combining a contraction of the Latin noun diabolus (devil) with a suffix derived from the name of the type genus of the tribe.

Notes. The relationship of Diablophthalmus to other Megophthalminae is uncertain. It is here tentatively placed in Megophthalmini based on the distinctly elevated and carinate frontal sutures characteristic of other members of the tribe. The development of the carinae varies among genera of the tribe. The type genus from Eurasia has very strongly developed carinae extended from the antennal ledge to the midline of the face. North American genera of Megophthalmini have these carinae much less well developed, although still extended to the midline. In Diablophthalmus , the carinae are developed laterally but obsolete medially.

Diablophthalmus resembles another South American tribe, Evansiolini (currently known only from the Juan Fernndez Islands), in lacking ocelli and hind wings and having elytralike forewings. The dorsal sculpture of the female first valvula also resembles that of Evansiola insularis Evans. However , Evansiolini lack the carinate lateral frontal sutures characteristic of Megophthalmini . The new genus also superficially resembles the Afrotropical Ulopella group of Ulopini ( Smith & Webb 2016) in having elliptical forewings. Within this group the new genus resembles Delopa Evans in having a prominent pair of anteriorly projecting processes on the head, a laterally depressed pronotum and convex scutellum, but lacks the main diagnostic characters of Ulopinae , e.g., body surfaces coarsely pitted, gena narrow, maxillary cleft and mesepisternal shelf present.

Diablophthalmus does not appear to be closely related to any other New World megophthalmine genus although its male genitalia suggest affinities to several South American species currently placed in the genus Agallia Curtis. Given the occurrence of the genus in Páramo habitats at high elevations in the northern Andes, it seems possible that Diablophthalmus represents an independent lineage distinct from the Megophthalmini faunas of other continents, derived separately from more widespread ancestors among the Agalliini .

Figures

FIGURE 1, Diablophthalmus. A–B, D. wygodzinskyorum sp. n., male holotype, dorsal and lateral habitus. C–E, D. marmoratus sp. n.: C–D, dorsal and lateral habitus; E, head and thorax in part, anteroventral view. Scale bars = 1 mm.

FIGURE 2. Diablophthalmus wygodzinskyorum sp. n. A–B, male genital capsule, lateral and ventral views. C–D, male genitalia, lateral and ventral views.

FIGURE 3. Diablophthalmus female terminalia. A, sternite VII, D. wygodzinskyorum. B, same, D. marmoratus. C–G, D. marmoratus: C, first valvula; D, same, enlarged view of apex. E, second valvulae; F, same, enlarged view of apex. G, gonoplac.