Libengaia Linnavuori, 1161

Viraktamath, C. A., Webb, M. D. & Yeshwanth, H. M., 2024, Opsiini leafhopper genus Libengaia Linnavuori (Hemiptera: Cicadellidae: Deltocephalinae) in Africa and India with description of one new subgenus and six new species, Zootaxa 5507 (1), pp. 104-122 : 105

Libengaia Linnavuori

Libengaia Linnavuori 1969:1160–1161 . Type species: Eutettix vermiculatus Melichar , by original designation.

Small species, 3.6–5.0 mm in length, yellow or ivory in colour with brown irroration.

Head including eyes as wide as or wider than pronotum. Crown either of uniform length throughout or medially slightly longer than next to eyes, with a shallow transverse furrow between ocelli, area anterior to furrow shagreen and posterior to it glabrous. Ocelli on anterior margin, contiguous with eyes or separated by a distance less than diameter of one ocellus. Frontoclypeus more than 0.75× as wide as long; transclypeal sulcus arched; clypellus elongate with sides parallel over basal 0.66, slightly expanded apically and a little produced beyond genal curve; genal margin concave below eyes. Pronotum twice as long as crown and about twice as wide as long; posterior margin transverse or shallowly concave; disc transversely and feebly striate, glabrous. Exposed mesonotum wider than long, either as long as pronotum or longer. Forewings with claval veins separate, connected by a cross vein near midlength; inner anteapical cell open; appendix well-developed. Metafemoral macrosetae 2+2+1; metatibial macrosetal formula AD 10±1, PD 18±1, AV 15±1. protibia with macrosetae 1+4 (AD+PD) and metabasitarsomere with four platellae.

Male pygofer lobe either more or less truncate posteriorly or conically rounded, with macrosetae on posterior half, without processes. Valve broadly triangular. Subgenital plate narrowed posteriorly, uniseriate row of macrosetae along lateral margin, with more lateral row of long hair-like setae, with (as in the nominate subgenus, Fig. 5B ) or without (as in subgenus Nandiana subgen. nov., Figs 9C , 10B ) apical membranous appendage. Connective Yshaped, stem longer than arms. Style robust; preapical lobe either poorly developed ( Fig. 4G ) or well-developed ( Fig. 4B ). Aedeagus with paired shafts directed posteriorly at base and then curving dorsally; gonopores apical; with or without lamellate expansion near midlength; preatrium elongate either short or long, extending ventrally and terminating in elongate posteriorly directed process forked either near base or near apex; preatrium with ( Fig. 5F ) or without ( Fig. 4E ) slender distally forked process.

Female sternite VII elongated or short and broad with posterior margin medially produced into bilobed median process or not. Valvula I with strigate sculpturing ventrally, turning into cells dorsally. Valvula II with teeth either prominent or weak confined to distal 0.33 length with one basal tooth.

Remarks. This genus belongs to the Hishimonus group of genera. The extension of the dorsal wall of the atrium into a short or long preatrium ventrad of the shafts distinguishes it from both Hishimonus and Hishimonoides . Libengaia closely resembles Naevus Knight from which it differs in the presence of a process on the preatrium near the base of the aedeagal shaft that Naevus lacks. Two species of Hishimonus namely, H. indicus (Sohi) and H. viraktamathi Knight resemble the species of this genus but lack the process of the preatrium and ventral extension of the atrium and preatrium. Libengaia has another feature that distinguishes it from the known species of Litura , namely, absence of a well-defined median transcommissural spot on the forewings. The three Indian species dealt with here differ from their African counterparts as follows: a) crown more or less parallel sided (medially longer in African counterpart), b) subgenital plate without membranous appendage, c) aedeagal shaft longer than or subequal to the preatrial processes (longer in the African species), and d) style apophysis differently shaped. In addition, the female sternite VII in the African species is very large, about 5× as long as the sternite VI, whereas in the Indian species it is not so large. These differences are quite significant suggesting that these two species groups may belong to different genera. However, here we recognize a new subgenus, Libengaia (Nandiana) for the inclusion of the Indian species.

Figures

FIGURE 4 A–G. Species of Libengaia (Libengaia) male genitalia. A–D, L. (L.) deemingi sp. nov.: A, genital capsule, lateral view; B, style, dorsal view; C, aedeagus, ventral view; D, aedeagus, lateral view. E–G, L. (L.) longistylus sp. nov.: E, aedeagus, lateral view; F, aedeagus, dorsal view; G, style, dorsal view.

FIGURE 5 A–F. Libengaia (Libengaia) trifida sp. nov., male genitalia. A, pygofer, lateral view; B, subgenital plate, ventral view; C, connective, dorsal view; D, style, dorsal view and apex of style, magnified; E, aedeagus, dorsal view; F, aedeagus, lateral view.

FIGURE 9 A–H. Libengaia (Nandiana) lamerallis Sunil & Meshram, metatibia and male genitalia: A, chaetotaxy of apex of metatibia, ventral view; B, pygofer, lateral view; C, subgenital plate, ventral view; D, connective, dorsal view; E, style, dorsal view; F, aedeagus dorsal view; G, aedeagal shaft, dorsolateral view; H, aedeagus, lateral view.

FIGURE 10 A–G. Libengaia (Nandiana) ramamurthyi sp. nov., male genitalia: A, pygofer, lateral view; B, style, valve and subgenital plate dorsal view; C, style, dorsal view; D, connective and aedeagus, dorsal view; E, aedeagus ventral view; F, connective and aedeagus, lateral view; G, aedeagus lateral view.