Abstract
The genus Cardiocondyla Emery, 1869 is a diverse group of ants in the subfamily Myrmicinae, with a total of 89 recognised species and subspecies recorded worldwide. A new species of the sima group C. zhoui sp. nov. is described herein, from China, based on worker morphology. The main diagnostic characters of this new species are as follows: 11-segmented antennae; occiput partly smooth and shining; clypeus broad and robust; mesosomal dorsum strongly convex and mostly smooth; metanotal groove absent; and petiolar peduncle long and slender. The new species is similar to C. sima Wheeler, 1935, but it differs in a smooth and shining occipital surface, evenly convex anterior clypeal margin, more elevated mesosomal outline, and more elongated petiolar peduncle. Additionally, a new synonymy is proposed: C. insutura Zhou, 2001, syn. nov. (= C. minutior Forel, 1899). Scanning Electron Microscope (SEM) images and high-resolution colour images of Chinese Cardiocondyla species are provided, with a taxonomic key to the Chinese Cardiocondyla species based on worker caste.