Lichen-feeding termites occupy a distinctive ecological niche. This feeding behavior underscores a complex interplay between the termites’ digestive abilities and the biochemical properties of lichens, known for their resilience and production of secondary metabolites. Understanding the dietary preferences and digestive mechanisms of these termites offers insights into their ecological roles and the evolutionary adaptations that enable them to exploit such a specialized food source. We conducted experiments with Constrictotermes cyphergaster, feeding it with different combinations of its natural food sources: wood bark and lichen from host trees. Gut microbial communities were analyzed through 16S rRNA sequencing and shotgun metagenomics. Our results revealed that a diet containing lichens induces a shift in microbiota composition and increases the abundance of genes encoding an AA3 enzyme with a role in lignin digestion. This study emphasizes the potential role of lichens in enhancing the digestive capabilities of termites, highlighting the intricate relationships between diet, gut microbiota, and enzymatic activity in Termitidae.

Arboreal termites are widely recognized for the ecological functions of their conspicuous nests, yet their interactions with the underlying soil remain poorly understood. Here, we provide the first comprehensive characterization of the hypogeal constructions associated with the arboreal termite Constrictotermes cyphergaster and evaluate their effects on soil properties across two contrasting pedological contexts in a semiarid environment in Brazil. We documented a consistent subterranean system composed of a central chamber and radiating tunnels connected to arboreal nests by a single gallery, revealing a poorly recognized vertical extension of the colony. The architecture of these hypogeal structures was independent of arboreal nest size, suggesting a functionally regulated subterranean component. By comparing soils collected from hypogeal constructions, soil beneath nests, and surrounding soil controls, we show that termite activity modifies soil chemistry and physical structure, but in a context-dependent manner. In hydromorphic Stagnosol soils, termite constructions increased porosity and pH, and base cation concentrations, indicating effects on soil structure and biogeochemistry cycling. In nutrient-poor Regosol soils, termite influence was primarily expressed through the accumulation of organic matter and nitrogen. Across both soil classes, hypogeal chambers exhibited higher nutrient content, revealing these structures as biogeochemical hotspots. Our findings demonstrate that C. cyphergaster functions as a dual-strata ecosystem engineer, integrating arboreal and subterranean environments through a cryptic yet ecologically consequential hypogeal system. These results redefine the ecological footprint of arboreal termites and highlight their potential role in enhancing soil functioning in semiarid landscapes.

Termites are known as wood consumers, although some species eat other substrates. Assessing resource selection is important to understanding their biology. The present study provides information on the foraging behavior of Constrictotermes cyphergaster (Blattaria, Termitidae) in a dry forest area of Caatinga in Brazil. We aimed to verify the frequency of resource exploitation by termites as a function of environmental and soil temperatures. We found no significant differences in resource exploitation as a function of temperature, which is interesting because this variable is often reported as modulating foraging activity in some other termite species. This species forages on open trails at high temperatures in the Brazilian semi-arid zone. Environmental changes may affect the dynamics of their behavior and, consequently, the ecosystem, since C. cyphergaster influences the carbon cycle and can modify the soil. Our study provides a basis for future research intending to understand the adaptations of this termite to live in the drylands.