In 1975 the Berlin aquarist Günter Daul collected during a holiday trip in Mexico some swordtails in the state of Quintana Roo and brought them to his homeplace successfully. This strain was called later erronously Xiphophorus hellerii Yucatan. However, the state of Yucatan is located west of Quintana Roo. Thus the strain should be named correctly Xiphophorus hellerii Quintana Roo; but the fish has been illustrated so often in the aquarium literature under the name of Xiphophorus hellerii Yucatan that a correction would lead only to unnecessary confusion. For all who are interested in the history of the fish we suggest the (German written) article: Wagenknecht, U. (2012): Der Yucatan-Schwertträger. Viviparos 1/2012: 26-29 (online here: http://www.lebendgebaerende-aquarienfische.de/media/files/Wagenknecht%20(2012)%20Der%20Yucatan-Schwerttraeger.pdf).
It is very interesting that this population has survived as a pure strain now for 38 years in the tanks of hobbyist. The genetics of this polychromatic variety are also very interesting. There do exist rather yellow-bellied females and rather white-bellied females. If one crosses a male that has much red colours with a yellow-bellied female, the offspring is pure red males and yellow-bellied females. If one crosses a rather blue-green male of the strain with a white-bellied females, they also breed pure. However, hobbyists usually breed with mixed schools to preserve the genetic variability of the strain.
Occasionally we have this interesting variety of wild swordtail as German bred in stock.
For our customers: the fish have code 476753 on our stocklist. Please note that we exclusively supply the wholesale trade.
Text & photos: Frank Schäfer