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Elephant Snout Fish

Elephant snout fish belong to a diverse group of fishes that comprise the family Mormyridae. All are freshwater species that are confined to tropical parts of the African continent. Some 150 species have been described so far. The group takes its common or English name from the animals' extended snout. This adaptation is taken to the extreme in the genus Gnathonemus which has a pendulous, trumpet-shaped snout. This species, like many other in the genus, feeds almost exclusively on small crustaceans. In some species, the snout is so modified that it possesses only a tiny mouth equipped with just a few, but relatively large, teeth. In some species the "trunk" is pendulous, while in others it may be held straight out from the head. Although this adaptation may, at first sight appear at odds to a predatory fish, because these animals often frequent muddy waters, this slender, highly tactile snout is ideally suited for detecting and grasping small prey that hide in vegetation or amongst rubble or mud on the base of streams and lakes.

All mormyroid fish possess specialized electric organs, a feature that is not unusual in species living in either deep or gloomy waters. In the elephant snout fish, this feature is probably related to helping the fish to move around and avoid obstacles, as well as assisting with the location of prey. By emitting a series of short, pulsed electrical signals, the fish is able to detect and avoid obstacles. In the same way, it can detect and pinpoint living animals that also give off a small electric field. In this way they are able to identify potential food items and avoid conflict with other electric-producing snout fish. Members of the family Mormyridae probably constitute the most diverse group of electric fishes; most swim by synchronous movements of the opposite dorsal and anal fins, thereby keeping the electric organs arranged along the sides of the body in perfect alignment with the body.

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Science EncyclopediaScience & Philosophy: Electrophoresis (cataphoresis) to Ephemeral