• Dr Norton Article: Notched, An Angelfish Deformity

    Dr. Norton's Articles - Part 18
    Reprinted with permission from:
    Dr. Joanne Norton
    Freshwater And Marine Aquarium magazine
    Notched - An Angelfish Deformity
    Photos and Text by Dr. Joanne Norton
    FAMA: March 1994, Vol. 17, #3

    Fig. 1: Flat-top angelfish.

    Fig. 2: A hole in the body is present under
    the dorsal fin. This fish also has a large
    notch in the lower body.

    An Angelfish Deformity
    Numerous desirable mutations in angelfish have appeared over the year. This article is about an angelfish deformity that I call "notched".

    There have been angelfish that are flat on top of the body (Fig. 1). A photo of a similar fish was published on page 47 of the March, 1981, FAMA. Occasionally, one can encounter an angelfish with a hole in the body (Fig. 2). A notched angelfish has part of the body missing, looking as if one or more pieces were cut off with a cookie cutter. These notched fish have been rare in my angelfish, occurring in approximately five individuals in 23 years.

    Notched angelfish may have one or more notches in the top of the body, one or more notches in the bottom of the body or notches in both the top and bottom of the body. Some notches are large and obvious whereas others are tiny nicks, as in the upper body notch in the fish in Fig. 10. In making progeny counts, I noted the larger, obvious notches. It is possible that some very small notches could have been missed. Some individuals have numerous notches (Fig. 3).

    A notched female (Fig. 4) appeared in my angelfish in 1989. I raised her F1 and F2 progeny in an attempt to find out whether notched is inherited. This female, mated to an unnotched male, produced four spawns in which every spawn had some notched fish. The totals from these were:

    • 496 normal
    • 61 top-notched
    • 78 bottom-notched
    • 27 top-notched and bottom notched.

    Fig. 3: Angelfish with many notches.

    Fig. 4: Notched female bred to unnotched male.

    Fig. 5: Top notched angelfish.

    Fig. 6: Top-notched angelfish.

    Also with split tail.

    Fig. 7: Bottom-notched angelfish.
    Also with split tail.

    The Total of 166 notched fish out of 662 is a much higher incidence of notched fish than I have seen in many thousands of angelfish that I have raised. Thus it appeared that the notched trait is inherited.

    Next I raised the F2, using a pair of F1 top-notched fish, an F1 pair of bottom-notched fish, and an F1 pair that were both top-notched and bottom notched. A top-notched pair, like the ones in Figs. 5 and 6, produced:

    • 123 normal
    • 28 top-notched
    • 19 bottom-notched
    • 24 top-notched and bottom notched.

    Fig. 8: Bottom-notched angelfish. Also
    with split tail.

    Three spawn from F1 bottom-notched fish (like those in Figs. 7 and 8) produced some notched individuals in every spawn. The totals were:

    • 152 normal
    • 12 top-notched
    • 45 bottom-notched
    • 16 top-notched and bottom-notched.

    Fig. 9: Top and bottom notch.

    Fig. 10: Top and bottom notch. The top notch
    is tiny. Also with split tail.

    An F1 pair that were notched on both top and bottom, like those in Figs. 9 and 10, produced a small spawn:

    • 14 normal
    • 3 top-notched
    • 1 bottom-notched
    • 2 top-notched and bottom-notched.

    In summary, when either one or both parents were notched, some of the offspring were notched. The original female, mated to an unnotched male, produced 25% notched offspring. The F2 were 37% notched from top-notched parents, 32% notched from bottom-notched parents, and 30% notched from parents that had both top and bottom notches.

    We now know that the notched trait in angelfish is inherited rather than a deformity resulting from injury. Therefore, notched angelfish should not be used as breeders if you do not want to raise any notched angelfish. In my opinion, notched angelfish should be discarded along with angelfish having deformed fins.