Menezes, L. R. d.; Franco Cairo, J. P. L.; Costa-Leonardo, A. M.; Clerici, M. T. P. S.; Barreto, I. d. C.; dos Santos, B. S. F.; Arab, A.

Termites are major decomposers in tropical ecosystems, relying on complex gut microbiomes to digest lignocellulosic substrates. In this study, we compared the gut microbiota composition and enzymatic responses to dietary shifts in two neotropical termite species with contrasting feeding strategies: the polyphagous Silvestritermes euamignathus and the litter-feeding specialist Cornitermes cumulans. High-throughput sequencing and enzymatic assays revealed that S. euamignathus maintained stable microbial communities and enzymatic profiles across diverse diets, including artificial and fiber-rich substrates. In contrast, C. cumulans exhibited significant shifts in bacterial abundance and reduced enzymatic activity under altered diets, particularly those differing from its natural litter-based diet. Functional gene predictions further indicated broader metabolic potential in S. euamignathus, particularly in response to complex substrates, while C. cumulans showed transcriptional suppression of polysaccharide-degrading enzymes. These results suggest that S. euamignathus benefits from a more flexible and functionally resilient gut symbiosis, enabling adaptation to heterogeneous or disturbed environments. In contrast, the narrower metabolic scope of C. cumulans may limit its capacity to respond to dietary change. Our findings highlight how feeding ecology shapes microbiome plasticity and digestive function in termites, with implications for understanding their adaptability under environmental stress and climate-driven shifts in resource availability.