﻿A key to genera of Dikraneurini from China, with description of a new species of Cornicola Ohara & Hayashi (Hemiptera, Cicadellidae, Typhlocybinae)

﻿Abstract The leafhopper genus Cornicola Ohara & Hayashi, previously recorded from Japan, is recorded from China for the first time and a new species, C.maculatus Xu, Dietrich & Qin, sp. nov., is described and illustrated, including its color polymorphism. This genus has male genitalia and hind wing venation similar to those found in Empoascini but it is more appropriately placed in Dikraneurini. A key to species of Cornicola is given together with a key to the genera of Dikraneurini from China.


Introduction
The tribe Dikraneurini is a diverse group and differs from other Typylocybinae leafhoppers in lacking an appendix in the forewing and in usually having the hind wing submarginal vein complete and extended past vein RA or RP basad along the costal margin (Dietrich 2005). However, some genera included in this tribe either lack the hind wing submarginal vein (Typhlocybella Baker) or have this vein reduced or obsolete at the apex of the costal margin and thus resemble species of Empoascini (Viraktamath and Dietrich 2011;Dietrich 2013;Ohara and Hayashi 2022). One such genus in the latter category is Cornicola Ohara & Hayashi, 2022, with C. mizuki Ohara & Hyashi, from Japan, as its type species. In this paper, a second species of Cornicola is described as new from southwest China, together with a key to Chinese Dikraneurini genera. To date, Dikraneurini contain 74 genera and 497 valid species distributed throughout the world (Dmitriev et al. 2022) of which 25 genera and more than 60 species occur in China and have been studied by Matsumura (1931), Anufriev and Emeljanov (1988), Dworakowska (1972Dworakowska ( , 1979Dworakowska ( , 1993a, Chou and Ma (1981), Zhang and Chou (1988), Zhang (1990), Zhang and Kang (2007), Zhang (2012, 2013), Yang et al., (2012), , Yang (2015, 2020), Huang et al. (2018), Kang et al. (2018), Qin et al. (2020).

Materials and methods
The specimens examined in this study were preserved in 95% ethanol stored for three years resulting in loss of the original color; they are now deposited in the insect collection of Illinois Natural History Survey, Champaign, Illinois (INHS). Morphological terminology used in this work follows Xu et al. (2021). Diagnosis. Cornicola is easily distinguishable from all other known Typhlocybinae in having the following combination of characters: (1) crown of head much narrower than pronotum and strongly elevated above anterior margin of pronotum (Figs 3, 6);
Notes. Ohara and Hayashi (2022) recognized that Cornicola is related to Igutettix Matsumura, 1932 and therefore placed the genus in Dikraneurini; and also compared the genus to Vilbasteana Anufriev, 1970, Koreoneura Hossain & Kwon, 2021and Sweta Viraktamath & Dietrich, 2011. However, the hind wing venation of Cornicola differs from the above-mentioned genera and instead resembles that of the Southeast Asian dikraneurine genera Rakta Dietrich, 2013 andAlbodikra Dietrich, 2013 in having the submarginal vein obsolete or reduced apically along the costal margin of the hind wing ( Fig. 10; fig. 2b, d in Dietrich 2013) and thus resembling that of Empoascini. Cornicola differs from these two genera in having an anteclypeus only slightly convex in both sexes (Figs 5,8) (strongly swollen and broad in males of Rakta and Albodikra). Despite a strong resemblance of the hind wing venation of the new genus to the common pattern in Empoascini and some additional similarities in the male genitalia (e.g., elongate style), Cornicola is clearly more closely related to Dikraneurini and may represent a transitional form between Dikraneurini and Empoascini.

Key to species of
Basal sternal abdominal apodemes parallel sided, reaching end of segment IV (Fig. 15). Male pygofer almost triangular in lateral view, dorsal margin with fingerlike process arising near distal third of dorsal margin and extended posterad, not reaching apex; distal lobe bearing 6 or 7 microsetae, ventral margin with 8 or 9 feeble microsetae, dorsal bridge occupying more than one-third length of pygofer (Figs 16,17). Anal tube gradually narrowed apically (Fig. 18). Subgenital plate longer than pygofer lobe in lateral view, broad basally, fused in basal two-thirds, tapered distally, apex rounded and strongly narrowing, with sparse scattered microsetae, 6-8 macrosetae arranged in single row along each dorsolateral margin near midlength (Fig. 19). Connective widest medially with subapical angular projection in lateral view, apical margin emarginate medially (Figs 20, 21). Style apodeme much shorter than apophysis, preapical lobe absent, without conspicuous setae, slightly broadened preapically, apex smooth, slightly broadened then tapered to hooklike tip, curved laterad (Fig. 22). Aedeagus with shaft broad at base, narrowed near middle and with broad dorsal distal lobe in lateral view; pair of slender distal processes extended laterad from adjacent gonopore, each with short dorsomedially directed spine and elbow-like bend near midlength with distal part curved dorsomesad in posterior view and anterodorsad in lateral view (Figs 23, 24).
Notes. This new species differs from Cornicola mizuki by the characters noted in the key.
Distribution. China (Chongqing). Etymology. The species name is derived from the Latin words 'maculatus', referring to the black spots on the crown and thorax.