Lyretail Swordtail

Geographic Origin and Biotope: Variety selected in breeding, not present in nature. The original strain comes from the fresh and alkaline waters of Central America.

Taxonomy and Morphology: Lyretail Swordtail (Xiphophorus hellerii). Long-finned variant. The main feature is the extension of the upper AND lower rays of the caudal fin (lyre shape), often combined with a veil dorsal fin.

Social Behavior: Slower due to fins. Maintains the lively and dominant temperament of the swordtail, but the large fins make it a clumsier swimmer, sometimes hindering courtship.

Coloration and Sexual Dimorphism: Available in many colors (red, green, neon). Males feature the complex "lyre tail" (two swords or extended rays) and the gonopodium (which in some extreme selections is so elongated as to make physical mating almost impossible).

Aquarium Setup: River Aquarium (Minimum 100 cm / 40 inches). Needs free space but less violent currents than the wild strain so as not to fatigue the veil-finned fish.

Diet and Feeding: Adaptable omnivore. Likes flakes, granules, algae and frozen foods (brine shrimp and bloodworms).

Water Quality: Hard and alkaline water. A high GH and a pH above 7.2 are fundamental. Acidic water corrodes their long and delicate fins.

Compatibility and Tankmates: Avoid "fin-nipper" tankmates like Tiger Barbs (Puntigrus tetrazona) or certain Tetras (Serpae), which would instantly destroy their lyretails.

Aquarium Reproduction: Ovoviviparous. Very often, due to the excessively elongated and deformed (hypertrophic) gonopodium typical of the Lyretail selection, males are functionally sterile. Non-Lyretail males are often used to fertilize Lyretail females.

Risks and Diseases: Fin Rot. The greatest risk for Lyretails is the fraying of their huge tails due to bacteria, stress or attacks from other fish.