Syncosmetus, Sharp, 1891

Jiang, Ri-Xin, Lopes-Andrade, Cristiano, Liu, Hao-Yi & Chen, Xiang-Sheng, 2022, An extraordinary new species of the genus Syncosmetus Sharp, 1891 (Coleoptera: Ciidae) from Yunnan, China, Zootaxa 5214 (2), pp. 294-300 : 299

Key to the described Syncosmetus species

(based on Lopes-Andrade, 2008 and Lopes-Andrade & Grebennikov, 2015)

1 Pronotum with two pairs of strong longitudinal ridges...................................... S. yunnanensis sp. nov.

- Pronotum without longitudinal ridges..................................................................... 2

2 Elytra subparallel-sided, with poorly raised longitudinal keels........................................ S. reticulatus

- Elytra suboval, with well-raised longitudinal keels........................................................... 3

3 First two elytral keels diverging far from elytral base................................................ S. japonicus

- First two elytral keels diverging close to elytral base......................................................... 4

4 Pronotum with surface between punctures not in high relief. Each elytron with second and third keels united at their apices.............................................................................................. S. perseus

- Pronotum with surface between punctures in high relief forming longitudinal striae. Each elytron with second and third keels not united at their apices................................................................................ 5

5 Pronotum with narrow longitudinal sulcus at midline; lateral margins usually narrow. Tegmen with basal portion membranous and bearing a sclerotized longitudinal stripe; apical portion not spoon-like and bearing a small emargination....... S. stheno

- Pronotum with broad longitudinal sulcus at midline; lateral margins usually broad. Tegmen with basal portion homogeneously sclerotized; apical portion spoon-like...................................................................... 6

6 Pronotum with margins visible for their entire lengths from above, coarsely crenulated; surface of longitudinal sulcus not microreticulate. Penis with lateral baculi not joined at base............................................... S. euryale

- Pronotum with only the posterior portions of margins visible from above, minutely crenulate; surface of longitudinal sulcus microreticulate. Penis with lateral baculi joined at base................................................ S. medusa