Are guppies the same as Endlers?

Are guppies the same as Endlers?

That’s a more difficult question to answer than you might think.

Scientific Studies

A paper publish on the Trinidad Guppy (Poecilia obscura) in 2009 indicated that the Endler Guppy (Poecilia wingei) is a separate species from the three known species of guppies known to exist in the world today; the Common Guppy or Millionfish (Poecilia reticulata), the Trinidad Guppy (Poecilia obscura), & the Endler Guppy (Poecilia wingei).

There are also several species of fish belonging to the family of Micropoecilia which are considered by some to be another form of Poecilia.

The Dispute

While genetic testing indicates that Endlers are a separate species, there are other ways that have been used in the past to distinguish one species from another.

One of the most recognized methods used is if a fish can readily cross breed with another species and if the offspring are fertile.

Endlers (Poecilia wingei) will easily cross breed with both the Common Guppy (Poecilia reticulata) and the Trinidad Guppy (Poecilia obscura) and the resulting offspring are fertile hybrids leading to the belief by some that Endlers are simply another form of the Common Guppy (Poecilia reticulata).

Endlers (Poecilia wingei) will also cross breed with a fish commonly known as a Swamp Guppy (Micropoecilia picta) however the resulting offspring are sterile and unable to produce offspring.

Because Endlers can so easily cross breed with other guppies and the offspring are fertile many believe that the Endler classification as their own species is simply for conservation purposes only and that Endlers are simply another form the Common Guppy (Poecilia reticulata).

Although there is some dispute as the the classification of the Endler Guppy (Poecilia wingei) is is officially considered it’s own species.

Endler and Guppy Differences

Endlers first caught the attention of John Endler due to the bright green metallic coloration found on many of the Endler strains.

This beautiful coloration is unlike the coloration found in any other guppy species or strain however there have been some Trinidad Guppies that have coloration that approaches that of Endlers.

Besides coloration there are also some small differences in the body shape and the in the Gonopodium (male sex organ).

One of the biggest difference we have seen is in behavior. This may be due to the fact that Endlers have been kept in captivity for a considerably shorter time than the Common Guppy.

Endlers are much more active than than the Fancy Guppy commonly sold in pet shops today. The males spend more time courting females rather than chasing females.

This courtship is quite interesting to watch as the males spread out and display their fins and coloration often bending their body and sometimes swimming backwards to capture the female’s attention.

So while the scientific community indicates that Endlers are not the same as Guppies you may wish to get your own Endlers and then you can decide for yourself.

References

Susanne Schories, Manfred K. Meyer & Manfred Schartl (2009). Description of Poecilia (Acanthophacelus) obscura n. sp., (Teleostei: Poeciliidae), a new guppy species from western Trinidad, with remarks on P. wingei and the status of the “Endler’s guppy”. Zootaxa 2266: 35–50