If your "endlers" were fabulous looking, chances are they are guppy/endler crosses. As a registered breeder of endlers, I maintain a pure wild type group of endlers in my tanks and can assure you that any truly amazing looking fish are likely to be hybrids. My pure stock is anything but amazing their color or similar characteristics.
On the other hand, fish like tiger endlers are very nice looking but are obviously crosses, at least to someone like me who keeps the real thing. I am afraid that endlers are going the way of the guppy. In the 1950s, I kept guppies that were close to being wild types but today those same fish are simply unavailable. It turns out that feeder guppies are probably as close to natural guppies as we will find today. They are not really wild type guppies but are as close as we ever see to a wild guppy these days. The same seems to be the fate of endlers these days. I keep wild endlers for species maintenance, but most people are not really interested in preserving wild type fish. Instead they seem to be interested in what can be done by introducing wild type stock into a domestic strain of guppy. The results can be dramatic and can be fixed in the strain fairly quickly. This means that things like tiger endlers can be fairly quickly established. For the average hobbyist, that means that a pretty fish can be obtained and can be expected to reproduce as a fixed strain fairly easily. That is what most hobbyists really want so their needs are being met nicely by guppy/endler crosses.