Betta Fish Anatomy

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Betta Fish Anatomy

Betta Fish Anatomy


Bettas are native to Southeast Asia where they are referred to as Siamese fighting fish. This species of Gourami is known for its bright coloring and elaborate fin patterns. In fact, most of it’s visual body mass is actually fin.


Eyes and Mouth


Betta fish have surprisingly good eyesight. Side placement is similar to most other species, but Bettas can see color and often react to their own reflection. The upturned, bulldog mouth looks much like a frown, but it allows the fish to skim off food from the surface. This is also a natural fighting mechanism. The teeth are relatively sharp, and Bettas are known for nipping the tails of fellow tank mates.


Fin Structure


Enthusiasts are typically drawn to the long, elegant and brightly colored fin structure. Betta fish have five different types of fins:


  • Caudal Fin –Known as the tail, this unpaired fin is used to propel the fish through the water. Breeding has creating a number of shapes, including the triangle, veil, half-moon and double tail.
  • Dorsal Fin –Unpaired and used for turning and stabilization. It sits up top towards the back of the body. Like the caudal fin, it’s made of several branches of cartilage that look much like veins.
  • Anal Fin –Unpaired and used for stabilization. It runs along the underlying length of the body, flaring out longer towards the rear.
  • Pectoral Fins –One on either side behind the gills. These are used to propel and turn through the water.
  • Ventral/Pelvic Fins –Flairs out beneath the head. This fin pair helps Bettas to ascend, descend, stop and perform sharp turns.


Operculum and Gills


The operculum is what covers the gills on either side of the fish. Gill tissue is fragile and highly susceptible to damage. Keep an eye on these openings and check for inflammation. This can be a sign of injury, but it’s more likely the result of poor water quality.