The "kings" of freshwater aquariums, Discus fish are known for their stunning looks. With stable warm temperatures and clear ...

Bettas come in a wide variety of tail types and colors, such as halfmoon, crown tails, and double tails. Adulthood: How Long Do Betta Fish Live? Adult bettas live a solitary life.

Fish in this genus either have long, elongated tail fins that resemble swords or regular, rounded tail fins. One popular species, Xiphophorus maculatus , is known as the southern platyfish or the ...

But they also use the long upper section of their tail fin, which can grow up to 10 feet (3 meters) long, to hunt. Related: Do wolves wag their tails? Thresher sharks have the longest tails in ...

The long structures seen in manta rays and their relatives function as an early warning system, rather than a defensive weapon. By Jack Tamisiea With hornlike facial fins and diamond-shape bodies ...