Gut Microbiota Reveal Ecological Adaptations in the Inquilinism of Ancistrotermes dimorphus and Its Host Macrotermes barneyi

Wenzhuo Lei¹Zhifang Qin¹Bao Jia²Wen Lu¹Juan Yang¹Qionghua Gao^1*

• ¹Guangxi University, Nanning, Guangxi Zhuang Region, China
• ²Termite Control of Nanning, Nanning, China

Inquilinism describes an interesting interspecific interaction in termite ecosystems wherein an inquiline species inhabits the host's nest structure. In this context, gut microbiota play a crucial role in mediating the ecological relationship. The facultative inquiline Ancistrotermes dimorphus (Termitidae: Macrotermitinae) frequently inhabits nests of the host Macrotermes barneyi but can also establish independent colonies. We used 16S rRNA sequencing to compare the gut microbiota of A. dimorphus and M. barneyi in independent and inquilinism nests, assessing microbial diversity and composition. Gut microbiota diversity increased under inquilinism, with greater microbial similarity between A. dimorphus and M. barneyi in shared nests. Furthermore, inquilinism altered microbial function, increasing taxa linked to environmental adaptation while reducing those involved in energy metabolism, suggesting potential metabolic trade-offs. Beta diversity analysis indicated that inquilinism drives the gut microbiota adaptation between the host and inquiline. These findings reveal how gut microbiota mediates host-inquiline interactions, advancing our understanding of microbial adaptation in social insect symbiosis.