Cave amphipods reveal co-variation between morphology and trophic niche in a low-productivity environment

Datasets used to explore co-variation patterns between morphological traits and trophic niche in co-occurring Niphargus amphipods from five groundwater caves of the Dinaric Karst, Europe. We quantified gnathopod size and shape by means of morphometric measurements and assessed isotopic niche, trophic position, and carbon signatures using nitrogen (δ15N) and carbon (δ13C) stable isotopes. We provide morphometric and isotopic data for Niphargus specimens, and isotopic data for food resources sampled in the caves.