Mormyrus longirostris

Mormyrus longirostris, commonly referred as the eastern bottle-nosed mormyrid, is a medium-sized ray-finned fish species belonging to the family Mormyridae. It was originally described by Wilhelm Peters in ''Monatsberichte der Akad. Wiss. Berlin'', 1852.

This species grows to a maximum length of 75 cm and can weigh up to 10 kg. The dorsal fin is more than twice the length of the anal fin. The dorsal origin is nearer to the tip of the snout than to the caudal fin base.

Ecology
It primarily feeds on weeds and insects, but also on small vertebrates, such as small fish and fish eggs. They hunt using electricity and can give a mild electric shock to defend itself.

Range and habit
M. longirostris can be found in abundance across the plains of Africa in freshwater habitats, including the lower and middle Zambezi, lower Sabi and Ludi rivers and in the Luapula-Moero-Bangwelo (Zambian Congo system). It inhabits the Ruvuma and Rufiji rivers in Tanzania, lakes Malawi, Tanganyika and Rukwa and other eastward-flowing rivers in Tanzania.

The species lives in caves and muddy areas with soft bottoms. It hides in weeds and characteristically forms small shoals.

Life history/behavior
Active mostly at night, it breeds during the summer rainy season, moving upstream in rivers after water has receded, with migrations at irregular intervals. Females carry 10,000–70,000 eggs at a time.

Relationship to humans
The fish is harvested for food with bait and hook.