Upside-down Catfish, also known as Synodontis nigriventris, is an interesting freshwater fish species. Native to certain parts of Central Africa, they are known for swimming upside down and other unique behaviors.
Upside-down Catfish are easily recognizable by their unique dark grey color and distinguishing upside-down swimming style. They also have an extremely elongated, downturned mouth tailored for scavenging the bottom of streams and rivers.
Unlike many fish that feed in schools, Upside-down Catfish are solitary creatures but will school together when food is present. Their natural diet usually includes zooplankton, insects, and other tiny organisms in their aquatic environment.
Although they may look small and fragile, Upside-down Catfish are tough and resilient. They are well adapted for living in tropical climates and can survive in water temperatures ranging from 68–86°F.
A distinct feature of their anatomy is their prominent adipose fin, a fatty fin between the dorsal fin and the caudal fin that helps provide stability and balance when swimming.
Upside-down Catfish can also recognize their owners and respond when called by name, making them popular pets with aquarists.
Unlike many other species, they stay small, reaching a maximum size of only 3-4 inches.
Reproduction in this species is unique, with females leading during mating season.
While females are generally larger than males, they tend to be less aggressive and stay alone in their territory.
It is believed that the upside-down swimming style of the Upside-down Catfish is an evolutionary adaptation for feeding. This helps make feeding more efficient as the mouth is close to the substrate.
The diet of these fish usually consists of tiny insect larvae, mollusks, and other small organisms found near the bottom of their aquatic environment. They don't require a large tank for captive care and are easily kept in tanks as small as 20 gallons.