Lyretail Swordtail Swordtail
Xiphophorus hellerii
About this strain
The lyretail mutation extends the top and bottom lobes of the caudal fin into elongated, symmetrical streamers, so instead of a simple sword projecting from the lower caudal lobe, both lobes are drawn out, giving the tail a lyre or double-sword silhouette. This fin form can be combined with virtually any body-color strain. The extended finnage is spectacular but does require extra attention to water quality — long fins are more prone to fin rot in suboptimal conditions. Also avoid aggressive or nippy tankmates. Males are still fertile despite the modified caudal structure.
Origin
The lyretail fin mutation has appeared independently across multiple livebearer species; in swordtails it was selectively fixed and popularized through European and Asian breeding programs, commercially established by the 1980s–1990s.