Out of Africa: novel source of small hive beetles infesting Eastern and Western honey bee colonies in China

Small hive beetles (SHB,Aethina tumidaMurray, Coleoptera: Nitidulidae) are parasites of social bee colonies endemic to sub-Saharan Africa and have become an invasive species. Even though the global spread of SHB seems inevitable, the origin of novel introductions and their impact on new host populations need to be investigated to foster mitigation. Here, we report a case of SHBs from China and use COI gene sequencing to trace their origin. Since July 2018, beetle infestations of Eastern (Apis cerana) and Western (Apis mellifera) honey bee colonies with clinical symptoms were repeatedly reported from two Chinese provinces. These infestations apparently had a severe impact onA. cerana. Using morphometrics, genetics and clinical symptoms in the field, the beetles were confirmed to beA. tumida. The DNA sequences suggest an introduction from a yet unidentified African source similar to the Philippines, but very different to any other previously reported SHB haplotypes. The establishment of SHB in China underlines the need to limit novel introductions. Given that Eastern honey bees and possibly otherApisspp. are susceptible to SHB infestations, our findings highlight the need for adequate protection measures of endemic Asian honey bees.

Automated summary

This study reports a case of SHB infestations in China and uses COI gene sequencing to trace their origin. DNA sequences suggest an introduction from an unidentified African source, similar to the Philippines but different from previously reported SHB haplotypes. The establishment of SHB in China underlines the importance of limiting novel introductions to protect endemic Asian honey bees.