Drabescus, Stal, 1870

Lu, Lin, Webb, Mick & Zhang, Yalin, 2019, A new species of the leafhopper genus Drabescus Stål (Hemiptera: Cicadellidae: Deltocephalinae) from China, with a checklist and key to species, Zootaxa 4612 (2), pp. 237-246 : 239-240

Key to species of Drabescus from China (male only)

Note. The following species are excluded from the key. D. albostriatus , D. extensus and D. fuscorufous (known only from the female) and D. atratus and D. notatus (types unknown, see Zhang & Webb, 1996).

1 Anterior margin of head broadly rounded in profile (Fig. 2B); aedeagus without basal apodeme, preatrium present (Fig. 2J).................................................................................. D. hainanensis sp. nov.

- Anterior margin of head angularly rounded ( Fig. 1B ); aedeagus with basal apodeme present or absent, preatrium absent ( Fig. 1G ) or present........................................................................................ 2

2 Aedeagal shaft without process.......................................................................... 3

- Aedeagal shaft with process............................................................................. 5

3 Style with lateral lobe absent................................................................... D. ineffectus

- Style with lateral lobe well developed..................................................................... 4

4 Aedeagal shaft with subapex expanded laterally in ventral view...................................... D. henanensis

- Aedeagal shaft fusiform in ventral view......................................................... D. cuspidatus

5 Aedeagal shaft with two pairs of processes................................................... D. quadrispinosus

- Aedeagal shaft with a single pair of processes............................................................... 6

6 Aedeagus with basolateral processes bifurcate apically........................................................ 7

- Aedeagus with basolateral processes not bifurcate apically.................................................... 11

7 Distal arms of basolateral processes of aedeagus widely divergent..................................... D. jinxiuensis

- Distal arms of basolateral processes of aedeagus not widely divergent............................................ 8

8 Aedeagal shaft expanded subapically in lateral view.......................................................... 9

- Aedeagal shaft not expanded subapically in lateral view...................................................... 10

9 Valve arciform; subgenital plate with inner margin moderately straight................................. D. lamellatus

- Valve triangular; subgenital plate with inner margin constricted with long apical process..................... D. furcatus

10 Aedeagal shaft relatively short, tapered to acute apex.................................................. D. gracilis

- Aedeagus long and cylindrical with apex rounded......................................................... D. lii

11 Head and thorax with yellowish medial longitudinal band; pygofer with ventroposterior margin denticulate............. 12

- Head and thorax without yellowish medial band; pygofer with ventroposterior margin not denticulate, with or without process.................................................................................................. 13

12 Connective with stem subequal in length to arms; aedeagal shaft with apex of basolateral processes rounded in lateral view............................................................................................. D. ogumae

- Connective with stem twice as long as arms; aedeagal shaft with apex of basolateral processes acute in lateral view................................................................................................. D. albosignus

13 Aedeagal shaft with apex of basolateral processes divergent in ventral view...................................... 14

- Aedeagal shaft with apex of basolateral processes moderately parallel or convergent in ventral view................... 20

14 Basolateral processes of aedeagal shaft longer than length of shaft in ventral view....................... D. formosanus

- Basolateral processes of aedeagal shaft shorter than or subequal to length of shaft in ventral view..................... 15

15 Processes of aedeagal shaft located at midlength of shaft or more distally........................................ 16

- Basolateral processes of aedeagal shaft not above........................................................... 17

16 Style apical process short.................................................................... D. limbaticeps

- Style apical process very long ( Fig. 1H )........................................................ D. albofaciatus

17 Connective short, nearly U-shaped....................................................................... 18

- Connective elongate, Y-shaped................................................................. D. convolutus

18 Basolateral processes of aedeagal shaft relatively slender............................................... D. nitobei

- Basolateral processes of aedeagal shaft relatively thick, width exceeding half diameter of shaft....................... 19

19 Basolateral processes of aedeagal shaft distant from basal shaft and divergent evenly in ventral view....................................................................................................... D. nervosopunctatus

- Basolateral processes of aedeagal shaft close to basal shaft and apically divergent in ventral view............ D. pellucidus

20 Aedeagal shaft relatively straight in lateral view............................................................ 21

- Aedeagal shaft curved C-shaped in lateral view............................................................ 26

21 Apex of aedeagus slightly expanded..................................................................... 22

- Apex of aedeagus not expanded................................................................. D. testaceus

22 Stem of connective more than twice as the length of arms............................................ D. piceatus

- Stem of connective less than twice length of arms........................................................... 23

23 Basolateral processes of aedeagal shaft with dorsal margin denticulate in lateral view.................. D. multidentatus

- Basolateral processes of aedeagal shaft not denticulate....................................................... 24

24 Basolateral processes of aedeagal shaft strongly convergent apically in ventral view.................... D. shillongensis

- Basolateral processes of aedeagal shaft lying close and parallel to shaft in ventral view............................. 25

25 Aedeagus with shaft very long, basolateral processes sinuate at midlenth not reaching apex of shaft in lateral view..................................................................................................... D. piceus

- Aedeagus with shaft moderately long, basolateral processes straight nearly reaching pex of shaft in lateral view. D. minipenis

26 Head and thorax bright yellow; aedeagus with basolateral processes moderately long, not reaching to near apex pf shaft................................................................................................ D. pallidus

- Head and thorax brownish and face yellowish in lower half; aedeagus with basolateral processes long, reaching to near apex of shaft....................................................................................... D. vilbastei

Figures

FIGURE 1. Drabescus albofasciatus Cai & He (male). A–B, habitus, dorsal and lateral view, respectively; C, head and thorax, dorsoanterior view; D. face; E. pygofer, lateral view; F–G, aedeagus, ventral and lateral view respectively; H, valve, subgenital plate and style, ventral view.