Domesticated edible insects are a sustainable protein source that has been gaining global attention. P. brevitarsis is one such species, and their larvae can also eat decaying organic waste and turn it into a plant-growth promoting mixture. But organic matter like this is high in lignocellulose, which is difficult to digest. In fact, these larvae lack the enzymes needed to break lignocellulose down on their own. So, researchers checked their microbiome for microbial genes able to fill in the gaps. The researchers established a comprehensive reference catalog of gut microbial and host genes. Between the two sets of genes, lignocellulose-degrading enzymes were abundant and highly diversified. P. brevitarsis larvae also selectively enriched their microbiome for lignocellulose-degrading microbes and had physiological adaptations that assisted in lignocellulose degradation. Namely, strong mouthparts for biomass grinding, an alkaline midgut for dissolving, and a mild stable hindgut to facilitate microbial fermentation. Most of the lignocellulose degradation-related sequences found here had not been previously described and could be explored for biotechnological applications. These results outlined the unique teamwork between P. brevitarsis larvae and their gut microbiota that allows them to break down lignocellulose.