Tenucephalus admirabilis, Zahniser, 2021

Zahniser, James N., 2021, Revision of the New World leafhopper tribe Faltalini (Hemiptera: Cicadellidae: Deltocephalinae) and the evolution of brachyptery, Zootaxa 4954 (1), pp. 1-160 : 95-96

Tenucephalus admirabilis n. sp.

( Figs. 59 , 85 )

Diagnosis. T. admirabilis can be distinguished from other species of Tenucephalus by a combination of the typical color pattern, styles bilaterally asymmetrical, style apophysis very long, aedeagus with short apical flagellar process, and unpaired dorsal process of connective-aedeagus expanded apically, with two small teeth at ~2/3 length, with preapical long thorn-like process, and apex wide, constricted preapically, and sharply pointed at apex.

Body. Male, 5.2–5.5 mm. Female, 5.7 mm to wing apex, 6.3 mm to ovipositor tip.

Color. With the typical color pattern. Brown lines above and below transverse white on anterior margin of head faint or partly absent. Forewing with bold bright yellow coloration on basal 3/5 of costa.

Male. Pygofer length slightly more than 2x height at midlength; tapering to somewhat angulate corner posterodorsally; posterior half with numerous macrosetae. Valve long; width about equal to median length; anterior margin produced medially. Subgenital plates large; lobate, broad through most of length; with single row of ~12–14 macrosetae sublaterally; with short fine hairs laterally. Style median arm produced anteriorly; apical halves of styles bilaterally asymmetrical; apophysis very long, arcuate with both apices pointing to the right side, with numerous short setae on right-hand margins. Connective-aedeagus with irregular asymmetrical unpaired dorsal process expanded apically, with two small teeth at ~2/3 length, with preapical long thorn-like process, apex sharply pointed and constricted preapically. Aedeagus long, tubular, slightly bending dorsally; with short apical flagellar process, length only 1.5–2x width of aedeagus at opening of gonopore; with two very small preapical teeth on ventral side. Phragma bulbous lobes somewhat elongate; with many short setae throughout. Segment X sclerotized lateroventrally.

Female. Pygofer with few macrosetae. Sternite VII long; width less than 2x median length; with deep asymmetrical cleft on right side.

Material examined. HOLOTYPE: 1♂, ARGENTINA: Misiones , Loreto, 10-XII-1931, A.A. Ogloblin [ USNM] . PARATYPES: 1♂, same data . 1♂, 1♀ same data except 18-XII-1931. [ USNM]

Etymology. The species name is an adjective meaning “strange, astonishing, or remarkable.”

Distribution. This species is known only from the type locality.

Remarks. T. admirabilis possesses bizarre male genitalia, with bilaterally asymmetrical styles and an extraordinary dorsal process of the connective-aedeagus. Three males were dissected, and all had the same configuration of the styles and dorsal process. Asymmetry is also expressed in the female sternite VII which has a deep cleft on only one side. However, only one female specimen is known. While it is not uncommon within Cicadellidae for single structures, like the aedeagus or an unpaired genitalic process, to be asymmetrical, this is perhaps the first known instance in Cicadellidae of the styles, paired structures which are normally mirror images of each other, expressing bilateral asymmetry. Other instances of bilaterally asymmetrical structures in Cicadellidae are known in many Typhlocybinae which have the left and right blades of the second valvulae different in shape, length, and number and shape of teeth. And within Auchenorrhyncha, bilaterally asymmetrical parameres (styles) are known in at least one genus of delphacid planthoppers, Malaxella Ding & Hu ( Qin & Zhang, 2009; Ren et al., 2015).

T. admirabilis appears to be most closely related to T. flagellifer which possesses a similar flagellar process at the apex of the aedeagus, and it is included in the informal – lingulatus species group.

Figures

FIGUIRE 59. Tenucephalus admirabilis n. sp. (A–B, D–H, J) standard views; A & B, male. (Q) base of aedeagus, phragma, and dorsal aedeagal process, dorsal view.

FIGUIRE 85. Distribution of Tenucephalus spp. in eastern South America.