The
lyretail platy has been in Saxony (Germany) since 1981
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By Dr. Dieter Gentzsch Taken from B.L.A. Issue n.6 – March 2004 |
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General There have already been reports about the breeding efforts concerning the
lyretail platies (Xiphophorus maculatus) (Gentzsch 1982). Inspired by
some foreign literary sources I have intended for some years now to
introduce once again the breeding history of the lyretail platies, which
has been shown on exhibitions since 1981 almost every year. The reprint
of an article by Norton (1972) about the breeding of lyretail platies in
2002 has now induced me to do so after all. The standard works about cultivated Xiphophorus forms (Axelrod and
Wischnath, 1991; Wischnath 1993) contain pictures of numerous swordtails
(Xiphophorus helleri) with lyretail fins, not however any pictures of
lyretail platies (X. maculatus). The same applies to the books of
Lambert and Lambert (1995) as well as Kempkes and Schäfer (1998).
However, the latter two publish beautiful pictures of the
lyretail-Variatus (X. variatus). This cultivated form has already
existed in Saxony since 1986 (Gentzsch 1988, Gentzsch 1996). In order to
avoid any confusion with the lyretail platy, I shall not elaborate on
the former in this paper. Similarly, also Axelrod und Gordon (1997) have
published pictures about lyretail-swordtails, although they comment as
follows: „…To date this characteristic has been limited to swordtails, no one
having been able to breed a lyretail platy, but it is merely a matter of
time, probably, until a similar trait shows up in platies.” Quite
obviously, the above standard works must have also disregarded the
article of Norton (1972). As it so happened, the lyretail platy has been regularly exhibited at
exhibitions organized by the work group Livebearers since 1981 (anonymous
1981-1989). The performance shows now organized by the DGLZ after the
re-unification of Germany continue to focus on these efforts. At the
International Performance Show for Livebearers, organized by the GGD in
Bretnig-Hauswalde on 19/20 October 2002, 93 pairs of cultivated
xiphohorus forms were exhibited. The prize-winners were a pair of
lyretail platies. We must thank Dr. Mathias Trauzettel, Andreas Wölfer,
Dieter Schöne, Günther Schramm and others for keeping this cultivated
form alive. The breeding history of lyretail
platies The following (and other) assumptions have been made right from the
outset: 1. The
activities were aimed at breeding a lyretail platy. 2. The
lyre-type fin shapes could only be taken from the female swordtail,
because the males are unable to play their part in the insemination
process without human interference due to the extremely long gonopodium 3. The
feature of the lyre-type fins will be dominantly hereditary. 4. As
soon as the cross-breeding between X. helleri and X. maculatus with
female lyretail descendants has been accomplished, male platies had to
be back-crossed so as to consolidate the platy type as soon as possible. The table below summarizes the history on the way to breeding a lyretail
platy. All animals not used for further breeding have been disregarded
for simplicity's sake. Breeding history of the lyretail
platy1)
(five litters between 21 Jan and 25 June 1979 with 72 animals)
(six litters between 20 Oct 1979 and 5 March 1980 with 98 animals)
(born on 6 January 1980) (four litters between 6 Oct 1980 and 16 March 1981 with 71 animals)
(six litters between 26 April and 7 July 1981 with 108 animals)
1) The following code letters, similar to those in the assessment
guidelines for Xiphos, have been used to enhance the presentation: H = X. helleri M = X. maculatus N = normal fins L = lyretail w = wagtail r = red c = wild-coloured The percentages reflect the calculated proportion of the hereditary
factor H and M. In 1978, the attempts to breed with six virgin HLr or HLc females,
respectively, and five MNr or MNwr males, respectively, lasted more than
half a year and failed eventually. The next step was therefore to
initially breed bastards with normal fins from an HNr x MNwr crossing
which, of course, extended the breeding history. The males, and only
they were required, were phenotypically very different as far as sword
length and courtship were concerned. A male with a particularly short
sword was used for the first crossing with 10 virgin HL females. Of the
only three fertile HL females (out of 14 L females from later breeds),
only one was fertile in four litters with one MNr male. So, this was the
first backcrossing on the basis of the platy type. The majority of
females gained from the breeding have probably already been fertile with
the MN males. The animals most similar to the platy type were then
backcrossed with the father (MNr) and two new males (MNwr), and the
descendants of the two new males were no less similar to the platy type
than the descendants of the father. The lyretail platies, shown for the
first time ever at the Ninth GDR Xiphoshow in Nordhausen in September
1981, originated from the litter of 26 April 1981 and were a pair of red
lyretail platies (MLr) as well as a pair with wagtail markings (MLwr).
The numbers in a litter of lyretail platies are lower than in a litter
of animals with normal fins, with an average of only 18 animals being
counted in the six litter between 26 April and 7 July 1981 (the numbers
in a litters ranged from 8 to 42 animals). It is important to say a few words about the hereditability of the
lyre-shaped fins. It has very often been described in the literature
about swordtails that the fin shape is a dominant feature, although the
percentage of animals with lyre-shaped fins is in most cases less than
50 %. This is probably due to the fact that some of the lyre-determined
eggs or embryos die. As far as my swordtails are concerned, I have
always been able to clearly distinguish between the animals with
lyre-shaped and normal fins. This is not the case with many lyretail
platies, as the litter of 26 April 1981 proved: It contained five
animals with normal fins and nine with lyre-type fins, although the fin
shape of four out of the latter nine were only slightly extended. This
shows already that the mechanism to pass on the feature of lyre-shaped
fins to following generations is much more complicated in the case of
the platy than in the case of the swordtail. Unfortunately, the
different fin shapes found in the numerous litters have not been counted
exactly, although the aim to breed lyretail platies was more or less
attained as early as in 1981. Under phenotypical aspects, these animals are platies, court quite
clearly like the X. maculatus and are completely fertile when crossed
with platy strains. It has been unavoidable over all these years to
select strictly, in order to keep and improve the feature of lyre-shaped
fins. It was also important not to make crossings with hi-fins and
brushtails, so that this beautiful cultivated form is not compromised
and does not degenerate, as it has partly happened with the
lyre-swordtail. Final comments After having gained 20 years of experience in the field of breeding
lyretail platies and in view of the Norton article of 1972 (or 2002,
respectively), it seems to be advisable to discuss a few things. This
cultivated form has been successfully kept alive with more or less great
difficulties over a relatively long period. All animals have originated
from the above mentioned breeding line, into which the most diverse
colours have been interbred. There have been, and still are, the
following colour shades of the lyretails about: red, red wagtail, yellow
wagtail, bleeding heart, yellow, tuxedo, black and many more. The
selection always had to be very strict. The hereditability of the
lyretail fins has not been as dominant as in the case of the X. helleri.
There have always been, and still are, numerous transitional shapes
between the normal and the lyretail fins. Some years ago, we had some
males with good lyretail fins and short gonopodia, but this strain has
never reappeared in the following generations. Unlike in the
observations of Norton (1972), the gender ratio of most litters was well
balanced, so that it was not necessary to look for males with a
sufficient number of female descendants. However, it has been observed
very often that one litter with a single colour shade consisted of one
gender only, as has been the case with platies with normal shapes and
genetic defects. Norton (1972 or 2002, respectively) mentioned several
times that hi-finned males have been admitted to interbreeding, which we
have strictly refused all the time: Our long-standing experience of
crossing hi-fins with lyretail swordtails has shown that this always
leads to a poor fin quality. As long as lyretail males cannot be bred
permanently with a normal gonopodium, there is no other way but to admit
males with normal fins to the breeding. In view of the lower size of the
X. maculatus as compared with the X. helleri, it would be advantageous
if the lyretail platy had a larger circulation. The main problem at the
moment is that a large number of animals only show rudimentary signs of
lyre-shaped fins, so that the strict selection will have to be continued
also in the future. Literature Anonym (1981-1989). Ergebnislisten der DDR-Xiphoschauen. Axelrod, Herbert R., Gordon, Myron. 1997. Swordtails keeping and breeding
them in captivity. t.f.h. Axelrod, Herbert R. , Wischnath, Lothar. 1991.
Sworttails and platies. t.f.h. Gentzsch, Dieter. 1982. Die Zucht des Lyratailplaty. AT 29(8): 269-271. Gentzsch, Dieter. 1988. Zucht des Lyratail-Variatus. ZAG
Lebendg. Zahnkarpfen (Sonderausgabe) : 20. Gentzsch, Dieter. 1996. Einige Bemerkungen zum Lyra-Platy und Lyra-Variatus.
DGLZ-Rundschau 4, 82-84. Kempkes, Michael, Schäfer, Frank. 1998. Lebendgebärende der Welt. Livebearers
and Halfbeaks. Verlag
A. C. S. Lambert, Derek, Lambert, Pat. 1995. Platies and swordtails. Blandford. Norton, Joanne. 1972(zit. von 2002). Breeding lyretail platies. Livebearer
News 2: 15-18. Wischnath, Lothar. 1993. Atlas of livebearers of the world. t.f.h.
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