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Endler's Livebearer
It's a Guppy!

Poecilia wingei reticulata

Discus Plague Virus


Published - 20111030, Revised:

In 1997 I was searching the internet for a new livebearer I had seen in my local fish store that was not for sale, called an Endler's livebearer (ELB). I could only find one reference to it on a message board, and no photos existed on the internet. None of the books in my fish book library had photos or a paragraph on the fish.

Luckily for me, through friends in the pet trade, I could track down a couple of dozen ELBs from someone with a breeding colony in one of his planted tanks.

I emailed Dr. John Endler and asked him if I were to send him a photo of the fish I had acquired and if he could confirmed if they were the livebearer named after him by an aquarium hobbyist. He confirmed that they were, indeed, the fish. I emailed John that I would write an article about the fish and post it on the internet. I asked him if he could provide me with his story about the fish and that I would include it in the article. After a few emails back and forth, a final article was developed about Endler's livebearer and posted on the internet with photos for the first time.

Since then, the popularity of Endler's livebearer has exploded, with multiple websites dedicated just to the ELB. Some hobbyists since then have made the trip to Laguna de Los Patos in Venezuela and other locations in the area to collect new wild stock.

There are now commercial hatcheries breeding ELBs for the aquarium trade, as well as some hybrids. Unfortunately for the aquarium hobbyist, usually only the male ELB is offered for sale through the trade. The good news is, that many local aquarium club members have breeding colonies they are often willing to share with other hobbyists.

Bad Science

In 2005 Fred Poeser, Michael Kempkes and Isaac Isbrucker published their work in Contributions to Zoology for giving ELB separate species status from Poecilia reticulata (guppy). They gave it a new species name (wingei). Their effort was a lot of work for nothing as it did not pass the peer review test to be accepted as new species. Evidence that ELB was indeed a guppy (Poecilia reticulata) had already been posted on the internet at least a year before they published their work.

California Tiger Endler's Livebearer
California Tiger Endler's Livebearer was first offered to the aquarium hobby in 2004. It took about a year to develop this breed of guppy so that it would breed true. It would not have been possible to develop this fish if Endler's livebearer were a separate species from Poecilia reticulata.

ELB meets the criteria for being included as a population of guppies. ELB does freely interbreed with other guppies. The cross of ELB with other guppies produces viable offspring that are fertile. Because of this fact, they cannot be a different species from Poecilia reticulata.

The definition of a species is a group of organisms capable of interbreeding and producing fertile offspring.

In 2004 the California Tiger Endler's Livebearer was published on Aquaworld Aquarium's website. This article outlined how the breed was developed from a cross between an ELB and a guppy. The hybrid was then line bred until the offspring bred true.

Endler's Livebearer is a Subspecies of Poecilia reticulata

Some obvious physical differences between the ELB and other wild guppy populations warrant giving the ELB subspecies status of Poecilia reticulata. ELBs have unique coloration in the geographic region in which they are found. Male ELBs have a more angular body and smaller caudal peduncle than other populations of guppies. Female ELBs are typically slightly more slender than other female guppy populations. ELB does meet the definition of subspecies. The definition for subspecies from Merriam-Webster is below:

A subdivision of a species: as a : a category in biological classification that ranks immediately below a species and designates a population of a particular geographic region genetically distinguishable from other such populations of the same species and capable of interbreeding successfully with them where its range overlaps theirs.

A named subdivision (as a race or variety) of a taxonomic species.

The ELB should be named Poecilia reticulata endleri in recognition of Dr. John Endler, who brought this fish to the world's attention. This would be the correct classification of Endler's livebearer.