What Does It Mean When Guppies Have Pin Tails?

Guppies are highly sought after aquarium fish. These hardy little tropical fish are low maintenance and are available in a range of beautiful colors. Guppies are bred with a variety of tail shapes, including veil-tails, lyre-tails, flag-tails and pin tails. The tail or caudal fin in pin tail guppies is round in shape, with a needle or pin shaped extension that lies in line with the body axis of the guppy.

  1. Ornamental Strains

    • Guppies are bred as ornamental aquarium fish and most of the fancy types look very different from their wild ancestors. Fancy guppies are highly sought after and prized for their tail shapes. This is particularly true of the male fish. You can distinguish ornamental guppy strains by their color and fin shapes. The various fancy types are typically named after their tail shape and the quality of the fish is related to how large and wide the caudal or tail fin is.

    Judging of Pin or Needle Tails

    • The basic form of the caudal or tail fin in a pin tail guppy is round and is equal to four-tenths of the length of the fish's body. The middle fin ray is elongated to create the characteristic needle or pin shape. The length of the fin, including the pin shaped extension, must correspond to the length of the guppies' body. When evaluating the pin tail, points are awarded according to the length of the tail in relation to the body length of the fish.

    Deduction of Points in Show Guppies

    • Points are deducted if the tail is less than six-tenths the length of the body. Points are also deducted if the pin extension is not in line with the body axis of the guppy. If the pin is shapeless or too broad and if the pin exhibits any curvature, points are also deducted. The pin shape is also not allowed to be serrated in any way. When measured, if the pin extension is longer than four-tenths of the body length, the judge also deducts points.

    Producing Pin Tails

    • Pin tails are normally produced through line breeding, which with ornamental guppies, is the practice of breeding offspring that possess the physical characteristics the aquarist requires, back to their parents. Experienced guppy breeders typically breed daughters back to their father. Aquarists also use selective breeding practices. In these cases, aquarists mate unrelated guppies that exhibit desirable characteristics with each other.