The morphology of the mouthparts and proventriculus of the wood-boring isopod Sphaeroma terebrans has been described, with particular reference to its possible filter-feeding abilities. Scanning electron microscopy revealed that while the mandibles might be designed to scrape pieces of wood from the cavity wall during boring, the rest of the mouthparts are better suited for microphagous feeding. Video observations of the mouthparts demonstrated the ability of S. terebrans to filter out particulate material from the water column, by means of the filtering setae on the first three pairs of pereiopods. The morphology of the gut was found to be largely similar to that of terrestrial herbivorous isopods; primary and secondary filter apparatuses were present, but the masticatory apparatus present in terrestrial herbivores was missing. The morphology of both the gut and mouthparts provides additional support for the assumption that wood is an unlikely food source for S. terebrans.

Driftwood was collected from Stuart Creek, North Queensland, to examine the relationship between the wood-boring isopod, Sphaeroma terebrans (Isopoda: Sphaeromatidae), and the wood-boring mollusc, Bankia australis (Bivalvia: Teredinidae). Broadly non-overlapping distributions in individual pieces of driftwood were found for S. terebrans and molluscan wood-borers at the study site.