How do fish-eating mormyrids differ from insect-eating mormyrids?

Within the Mormyridae family, differences between fish-eating (piscivorous) and insect-eating (insectivorous) species are primarily reflected in their head and mouth morphology, which are adapted to their specific feeding strategies.1

• Insect-eating mormyrids: These species typically possess a small mouth located at the tip of a long, curved, tubular snout. This specialized anatomy allows them to effectively probe for prey among rocks or within soft mud.1
• Fish-eating mormyrids: In contrast, piscivorous species are characterized by having larger mouths and shorter snouts. While their jaws are not protrusible, their larger gape is an adaptation suited for consuming fish.1

These morphological variations allow different mormyrid species to occupy distinct ecological niches within their freshwater habitats.12