A new species of the leafhopper genus Diomma Motschulsky (Hemiptera, Cidadellidae, Typhlocybinae) from China

Abstract In the present paper, a new species is added to the genus Diomma Motschulsky (Hemiptera: Cicadellidae: Typhlocybinae) from Southwest China, Diomma pincersa sp. n. At the same time, a key can distinguish all Chinese species of the genus is provided.


Introduction
Th e leafhopper genus Diomma was established by Motschulsky in 1863(Dworakowska 1981Chiang and Knight 1990). Diomma belongs to the tribe Erythroneurini (Typhlocybinae) with Diomma ochracea Motschulsky, 1863 as its type species. Th e genus consists of three subgenera: Diomma Motschulsky; Bunyipia Dworakowska and Dilobonota Dworakowska. So far, all species occurring in China belong to the subge-nus Diomma, which distributed only in Oriental region. A new species from Guizhou Province, China is described and illustrated. A key to Chinese species of Diomma is given. All specimens examined are deposited to the collection of the Insititute of Entomology, Guizhou University, Guiyang, China (GUGC).

Diomma Motschulsky 1863: 102
Type species: Diomma ochracea Motschulsky, 1863. Description. Body yellow or brownish yellow, more or less fl attened. Head almost equally broad as pronotum. Crown anterior margin produced medially. Pronotum with width greater than length. Vertex and pronotum usually ornamented with dark spots or stripes. Scutellum small, triangular; transverse impression distinct. Forewing apical veins free or 3rd apical cell stalked; 4th apical cell smallest. Hind venation reduced, submarginal vein poorly developed.
Abdominal apodemes long and narrow. Pygofer large and broad, with numeous long setae at caudal margin and baso-ventral angle respectively. Subgenital plate extending beyond pygofer, with several microsetae on dorsal margin and with few of long macrosetae on outer surface. Pygofer dorsal appendage with distinct basal suture, but not movably articulated or immovably fused to margin, without basal suture. Central part of style very thick; preapical lobe prominant, sensory pits situated at preapical portion. Aedeagal shaft curved ventrally, usually with a obvious big process between preatrium and base of shaft. Gonopore terminal or subapical. Connective V-or Y-shaped; two lateral arms very long; central lobe absent or vestigial.

Key to Chinese species (♂) of the genus Diomma
Measurement. Body length males 2.8 mm.
Remarks. Th e new species can be distinguished from other species of the genus by its unique aedeagus's structure (Figs 8, 9).