Synopsis of Ant Genus Proceratium Roger, 1863 from China (Hymenoptera, Formicidae), with Description of Seven New Species

The genus <i>Proceratium</i> comprises rare but ecologically significant cryptobiotic predators of temperate and tropical forest litter. The group is known for its abdomen which can curl dorsally >90° relative to the body axis. <i>Proceratium</i> includes 130 described species worldwide. In China, seven species have been recorded, yet recent surveys repeatedly reveal morphologically distinctive undescribed taxa, indicating a still-underestimated diversity of <i>Proceratium</i>. In this study, seven known Chinese species of the ant genus <i>Proceratium</i> Roger, 1863 are reviewed: <i>P. bruelheidei</i>, <i>P. itoi</i>, <i>P. japonicum</i>, <i>P. kepingmai</i>, <i>P. longmenense</i>, <i>P. shohei</i> and <i>P. zhaoi</i>. The species <i>P. longigaster</i> is removed from the ant fauna of China. Additionally, seven new species are described: <i>P. crassopetiolum</i><b>sp. nov.</b>, <i>P. digitospinum</i><b>sp. nov.</b>, <i>P. planodorsum</i><b>sp. nov.</b>, <i>P. quandratinodum</i><b>sp. nov.</b>, <i>P. rugiceps</i><b>sp. nov.</b>, <i>P. shanyii</i><b>sp. nov.</b>, and <i>P. spinosubum</i><b>sp. nov.</b> An illustrated key to Chinese species based on workers is also provided.