Cyclogethes, Kirejtshuk, 1979

Liu, Meike, Wang, Xinyue, Yang, Xingke, Huang, Min, Audisio, Paolo, Gardini, Pietro & Sabatelli, Simone, 2024, A new Chinese Cyclogethes pollen beetle, with an updated key to species of the genus and notes on its phylogenetic positioning (Coleoptera: Nitidulidae: Meligethinae), Zootaxa 5406 (2), pp. 359-372 : 367-370

Key to identification of species of the genus Cyclogethes

[from Jelínek (2000b), updated and modified; Figs 5 , 6 herein re-inked and slightly modified from Jelínek (2000b) and Kirejtshuk (1979, 1980)].

1 (2) Metatibiae peculiarly narrow (ratio MTLE/MTWI= 4.5–4.7), in both sexes markedly sinuated along their inner edge ( Figs 2f–g ), their outer edge without a series of spinules (only with a short series of very small hairs distad). Elytra without any trace of transversal strigosity, distinctly longer than their combined width, ratio ELLE/ELWI≈ 1.15 ( Figs 1a , 2a ). The whole body yellowish-brown, at most with barely darker, infuscate elytral discal portion. Male genitalia and ovipositor as figured ( Figs 1b–d ). Body length: 2.2–2.5 mm. SW China (Yunnan) ( Fig. 4 )................................... C. tibialis sp. nov.

2 (1) Metatibiae in both sexes wider (ratio MTLE/MTWI= 2.7–3.6), simply arcuated along their inner edge and not sinuated (Figs 11, 22–23 in Jelínek 2000b; Figs 6e–g herein), their outer edge with a series of normal, dense and moderately long spinules. Elytra with more or less distinct traces of transversal strigosity, shorter than or at most as long as their combined width (ratio ELLE/ELWI≈ 0.8–1.0)................................................................................. 3

3 (4) Elytra nearly as long as their combined width, ratio ELLE/ELWI ≈ or <1.0. Meso- and metatibiae markedly narrower than in the following species, ratio MTLE/MTWI= 3.5–3.6 (Fig. 22 in Jelínek 2000b; Fig. 6f herein). Prosternal process narrowed apically ( Fig. 5 in Jelínek 2000b; Fig. 6a herein). Body yellowish-brown, elytra, metaventrite and abdomen blackish-brown to blackish, tips of elytra and apical margin of hypopygium yellowish. Male genitalia as figured (Figs 16–17 in Jelínek 2000b; Figs 5e–f herein). Ovipositor: Fig. 84 in Kirejtshuk 1980; Fig. 6h herein. Body length: 2.1–2.3 mm. N India (Uttar Pradesh, Uttarakhand), Nepal ( Fig. 4 )..................................................... C. aldridgei Kirejtshuk, 1980

4 (3) Elytra shorter than their combined width, ratio ELLE/ELWI <1.0. Meso- and metatibiae markedly wider than in the preceding species, ratio MTLE/MTWI= 2.8–3.0 (Figs 11, 23 in Jelínek 2000b; Figs 6e, g herein). Prosternal process not narrowed apically ( Figs 6 –7, 9 in Jelínek 2000b; Figs 6b–d herein)............................................................. 5

5 (6) Prosternal process narrow, parallel-sided ( Fig. 6 in Jelínek 2000b; Fig. 6b herein). Male: tegmen with deep V-shaped excision and smooth ventrolateral margins, median lobe of aedeagus broadly arcuately emarginate apically (Figs 18–19 in Jelínek 2000b; Figs 5g –h herein). Ovipositor: Fig. 43 in Kirejtshuk 1979 and in Fig. 6k herein. Length 1.9–2.1 mm. Vietnam, N Thailand, NE India (Darjeeling), SW China (Yunnan, Guizhou) ( Fig. 4 ).............................. C. abnormis Kirejtshuk, 1979

6 (5) Prosternal process wider, and with more or less arcuate lateral margins (Figs 7, 9 in Jelínek 2000b; Figs 6c–d herein). Male: tegmen more elongate, its ventrolateral margins with series of incisions (Figs 12–13, 20 in Jelínek 2000b; Figs 5a–b, 5i herein).............................................................................................. 7

7 (10) Elytra transversely strigose with distinct, sometimes oblong, punctures.......................................... 8

8 (9) Male: genitalia (Figs 34–36 in Kirejtshuk 1979; Figs 5k–m herein) similar to those of C. orientalis , tegmen with shallow apical emargination reaching about one fifth of its length, incisions of ventrolateral margins situated more proximally than the bottom of the emargination; median lobe of the aedeagus parallel-sided, slender, with narrow terminal protuberance gently curved in lateral view. Ovipositor: Fig. 37 in Kirejtshuk 1979; Fig. 6j herein. Body length 1.9–2.1 mm. Vietnam, SW China (Yunnan) ( Fig. 4 ).................................................................... C. spathulatus Kirejtshuk, 1979

9 (8) Male: tegmen (Figs 12–13 in Jelínek 2000b; Figs 5a–b herein) with apical emargination reaching about two fifths of its length, ventrolateral margins with series of incisions situated immediately at the tips of lateral lobes; median lobe of aedeagus without terminal protuberance (Figs 14–15 in Jelínek 2000b; Figs 5c–d herein). Ovipositor unknown. Body length 1.7–1.8 mm. NW Thailand ( Fig. 4 )................................................................ C. fuscipennis Jelínek, 2000

10 (7) Elytra transversely strigose without distinct punctures. Male: genitalia resembling those of C. spathulatus , tegmen with apical emargination reaching about one third of its length and series of incisions on ventrolateral margins situated besides the bottom of the incision; median lobe of the aedeagus slender, parallel-sided with narrow terminal protuberance strongly hooked in lateral view (Figs 20–21 in Jelínek 2000b; Figs 5i–j herein). Ovipositor: Fig. 30 in Kirejtshuk 1979; Fig. 6i herein. Body length 1.9–2.1 mm. Vietnam, N and S Thailand ( Fig. 4 )..................................... C. orientalis Kirejtshuk, 1979

Figures

FIGURE 1. a. Habitus of the male holotype of Cyclogethes tibialis sp. nov. b–c. Tegmen and median lobe of the aedeagus of Cyclogethes tibialis sp. nov. d. Ovipositor of Cyclogethes tibialis sp. nov. Scale bars: 1 mm (a); 0.2 mm (b–d).

FIGURE 2. a. Habitus of the male holotype of Cyclogethes tibialis sp. nov. b. Left antenna (pubescence not considered) of Cyclogethes tibialis sp. nov. c. Outline of the prosternal process of Cyclogethes tibialis sp. nov. d. Male left front tibia of Cyclogethes tibialis sp. nov. e. Male left middle tibia of Cyclogethes tibialis sp. nov. f–g. Male (f) and female (g) right hind tibiae of Cyclogethes tibialis sp. nov. h–i. Male (h) and female (i) pygidium of Cyclogethes tibialis sp. nov. Scale bars: 1 mm (a); 0.2 mm (b–i).

FIGURE 4. Distribution map of the six known species of the genus Cyclogethes. The map includes all records previously published by Kirejtshuk (1979, 1980), Kirejtshuk & Kabakov (1997), Jelínek (2000b), Jelínek & Audisio (2007), those listed by Chen (2013) and Liu (2019), and the new records published herein.

FIGURE 5. (original drawings from Kirejtshuk 1979, 1980 and Jelínek 2000b, re-inked and slightly modified) a. Tegmen (dorsally) of Cyclogethes fuscipennis. b. Tegmen (laterally) of Cyclogethes fuscipennis. c. Median lobe of aedeagus (dorsally) of Cyclogethes fuscipennis. d. Median lobe of aedeagus (laterally) of Cyclogethes fuscipennis. e–f. Tegmen and median lobe of aedeagus (dorsally) of Cyclogethes aldridgei. g–h. Tegmen and median lobe of aedeagus (dorsally) of Cyclogethes abnormis. i– j. Tegmen and median lobe of aedeagus (dorsally) of Cyclogethes orientalis. k. Tegmen and median lobe of aedeagus (laterally) of Cyclogethes spathulatus. l–m. Tegmen and median lobe of aedeagus (dorsally) of Cyclogethes spathulatus. Scale bar: 0.2 mm (a–m). Note: The authors inferred that the scale bar of Figs 34–36 in Kirejtshuk 1979 may be incorrect. It was inferred from the context that it should be 0.25 mm instead of 0.5 mm, so corrections were made in k, l, and m of Figure 5.

FIGURE 6. (original drawings from Kirejtshuk 1979, 1980 and Jelínek 2000b, re-inked and slightly modified) a. Prosternal process of Cyclogethes aldridgei. b. Prosternal process of Cyclogethes abnormis. c. Prosternal process of Cyclogethes orientalis. d. Prosternal process of Cyclogethes fuscipennis. e. Left posterior tibia of Cyclogethes fuscipennis. f. Left posterior tibia of Cyclogethes aldridgei. g. Left posterior tibia of Cyclogethes abnormis. h. Ovipositor of Cyclogethes aldridgei. i. Ovipositor of Cyclogethes orientalis. j. Ovipositor of Cyclogethes spathulatus. k. Ovipositor of Cyclogethes abnormis. Scale bar: 0.2 mm (a–k). Note: The authors inferred that the scale bar of Figs 37, 43 in Kirejtshuk 1979 may be incorrect. It was inferred from the context that it should be 0.25 mm instead of 0.5 mm, so corrections were made in j and k of Figure 6.