Taxonomic study of the Macrolycus gracilis group (Coleoptera: Lycidae), with descriptions of four new species from China

Macrolycus Waterhouse, 1878 is a lycid genus endemic to the East Palaearctic region and the northern part of the Oriental region; nearly half of the described species are distributed in China. Although the taxonomy of Macrolycus has made some progress in recent years, many species remain undescribed in the Chinese fauna. In the present study, the Macrolycus gracilis group is reviewed, and four new species are discovered and described from China, viz. M. nigricollis sp. nov., M. graciliramus sp. nov., M. breviramus sp. nov. and M. acutiapex sp. nov. The habitus of the male or of both sexes, and the male genitalia, are illustrated. In addition, a distribution map and a key to the species of the M. gracilis group are provided.