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Hundreds of kilometres from the legendary city of Cumaná, we found (what would prove to be) millions of Endler’s Guppies. The poor Luis didn’t know what happened: two idiotic Europeans, dancing and shouting as if they won the Football World Cup (Dutchman and a German, how was that possible?), just because they caught some tiny, nearly invisible little fishes. Little fish that were swimming there by the millions, so for Luis there was absolutely nothing special about them. In the region, broadly about 50 by 100 kilometres wide, we nearly couldn’t catch anything else but Endler’s Guppies: in every clear stream, all the muddy drainage canals, all ditches along the road, brackish lagoons, everywhere but in the freshly puddles of rainwater.
It took us a couple of days to find out the exact range for this little fish. When we were north of the mountain range, we found our fish, every trip over that range resulted in Common Guppies. The whole Campoma region was swarmed by this fish, just over the hills in the Orinoco drainage… only Common Guppies.
What was new for us was that this Guppy was as variegated as the Common Guppy. No, we lie: it is far more variable than the Common Guppy. Not only have we found the beauties with the “Endler comma”, there were also the “normal” spotted Guppies, or completely green ones, or completely yellow (which made them golden, because all colours were metallic, always). The tail fin could be normal, but could have bottom swords, or top sword, or double swords. Dorsal fins had colours or were without, gonopodia could be black or not. There was no end to the variation, except that all colours were metallic! Just exquisite. Even the female had this metallic sheen over their bodies.
After only three days, an important detail became apparent. The “Endler comma” was only found in the Campoma lagoon and it surroundings, the normal spotted variety was found in the region near the city of Carúpano. Therefore, the populations bordering the area were the Common Guppy resided were very differently pigmented (because of the comma), whereas the populations far away from the Common Guppy resembled them the most: normal spots and patterns (but metallic). This phenomenon is known in biology as character displacement: two populations of related species resemble each other in the area were they do not co-occur, but tend to be different in areas were they possibly do co-occur. This was our proof! This mechanism only occurs between two species, therefore, the Campoma Guppy had to be a different species! We cracked the riddle, we solved the code…
It took us some time since, but we finally officially described “our” Guppy (together with Dr Isaäc Isbrücker from the University of Amsterdam) as Poecilia wingei Poeser, Kempkes & Isbrücker, 2005. We named it after Dr Øjvind Winge, a Danish geneticist that, although a founding father of modern gene-technology, is strangely anonymous to most people. Moreover, he has done pioneering work on Guppy genetics and inspired Michael and Fred enormously in their efforts to “understand the Guppy”. Together with the Common Guppy, the Campoma Guppy represents the subgenus Acanthophacelus Eigenmann, 1907. After 146 years, the Guppy is not alone in taxonomy anymore.
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