Myron Gordon's swords

Dr. Myron Gordon did extensive experimentation on swords in the mid 20th century in fields of genetics and cancer. This is a photo accompanying an article he wrote and what's significant about it is, it's widely believed that only X. montezumae had a long "sword" but this photo of X. helleri clearly shows that is not actually true. Long sword X. helleri do in fact exist. It's a pity the exact location in Mexico was not given.









Yucatan

Xiphophorus hellerii “Yucatan” with the present dominant male, there is also a smaller male and one of the "females" is a late blooming male that just started to show a bit of a sword.


Hybrid?

This fish showed up in a German store as "Yucatan 2". People that have gone to Yucatan have brought swords back but none looked like this. The very long tail and coloration people have said, suggests it's probably a hybrid with X. montezumae.