The title of this post is perhaps a little misleading; it is intended to indicate that the species recently scientifically described as Myloplus sauron has been known in the hobby as Myleus schomburgkii for around 100 years. However, M. schomburgkii still exists. Back in 2004, the genus Myloplus was separated from Myleus and M. schomburgkii was placed under Myloplus. Until June 2024, all Myloplus with a black vertical band on the flank were classified as M. schomburgkii.
A recent revision of the group revealed that there are not one, but three species with a vertical black bar on the body flank. Aquarists have long been familiar with “broad-banded” and animals with narrow bands. The latter are the most common in the hobby, not least because they are bred in SE Asia for the ornamental fish market. The species with a narrow body band has now been renamed and described as Myloplus sauron. It originally comes from the Rio Xingu in Brazil.
Broad-banded Myloplus are widespread in Brazil and Venezuela in the middle and lower reaches of the large river systems of the Amazon and Orinoco. This is the “true” Myloplus schomburgkii. However, there is a second broad-banded Myloplus that occurs in the western Amazon basin of Peru and Brazil, i.e. the upper areas. This new species is now called M. aylan. It is not easy to distinguish between M. schomburgkii and M. aylan, so anyone interested should refer to the free and freely accessible original scientific description: https://www.scielo.br/j/ni/a/fFG9HTqKTjCs4Z4W3MxwSLJ/?format=pdf&lang=en
In any case, the “true” M. schomburgkii is the most colorful of the three species. M. aylan is more discreetly colored. While in M. schomburgkii the red coloration of the male can extend over the entire body, in male M. aylan it is essentially limited to the throat area. M. sauron shows the least color. The areas around the gill cover and front breast are only yellow-orange, sometimes reddish (especially in young specimens). Young sexually mature wild-caught males developed black-colored zones in the belly area at a size of 12-15 cm.
By the way: the three show such serious differences in the DNA structure that it is quite likely that they will end up in different genera in the future. And there are several color forms of M. schomburgkii (the “real” one) with clearly different colors. It is quite likely that some of these will be separated as separate species in the future.
You can find photos of M. aylan here: https://www.aquariumglaser.de/en/fisharchive/myloplus-schomburgkii-big-black-stripe-2/
You can find photos of M. schomburgkii here: https://www.aquariumglaser.de/en/fisharchive/myleus_schomburgkii_en/
We can offer the “new” Myloplus sauron very regularly, the other species are only offered very occasionally. All Myloplus can grow quite large, approx. 30-40 cm. They are magnificent animals, but only suitable for owners of really large aquaria. There they are very long-lived. One disadvantage of these fish is that they regard pretty much any aquatic plant as additional food.
For our customers: M. sauron has code 270501 (3-4 cm) and 270505 (8-11 cm) on our stocklist. Please note that we only supply the wholesale trade.
Text & photos: Frank Schäfer