From Stan & Debbie Hauter,
Your Guide to Saltwater Aquariums.
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We had stated in our previous "Can Moray Eels Live in Freshwater" article that, " NO, you cannot put a true saltwater Moray Eel of any kind into fresh or brackish water and expect it to live. They are just that, saltwater fish!! W ith all the research we have done about this, we are not aware of ANY "true" freshwater Moray Eels". Since writing this it has been brought to our attention that, in fact there are!

An informational web page link from the Aquaria Central Brackish Species Profiles section was e-mailed to us about the Echidna rhodochilus, commonly called the Freshwater Moray Eel. Investigating further we learned that this Eel is primarily a brackish water Eel that does enter freshwater, and can adapt to marine conditions as well, so we dug deeper to learn more about this Eel using the following taxonomy resources:

Family - Muraenidae (Moray Eels)
--> Subfamily - Muraeninae
--> Order - Anguilliformes
--> Class - Actinopterygii (Ray-Finned Fishes)
--> No. of Genera: 15
--> No. of Species: 200

Using the List of Nominal Species of Muraenidae from the fishbase.org database, which includes profiles and photos, we found that most Eels in this family are reef-associated; marine species. However, we discovered that Echidna rhodochilus is not the only species that inhabits fresh and/or brackish waters, there are 10 others. O f the Eels shown on this list it appears that Gymnothorax polyurandon , also commonly referred to as the Freshwater Eel, is actually just that. It lives in lentic (living in swamp, pond, lake or any other standing water) and lotic (applies to or pertaining to running water; living in a brook or river) freshwater areas. In other words, it is primarily a freshwater residing Eel. But, it is also estuarine (living mainly in the lower part of a river or estuary; coastlines where marine and freshwater meet and mix; waters often brackish) and marine residing. Aside from this Eel, and Echidna rhodochilus , the others seem to primarily reside in brackish and/or marine conditions, with the Strophidon sathete sometimes found in freshwater rivers and inner bays. (All definitions were obtained from the fishbase.org Glossary)

To help save you the time of having to go down and view every Eel on the fishbase.org's List of Nominal Species of Muraenidae , we compiled a Freshwater/Brackish/Saltwater Moray Eel Species List for you. With this list, at a quick glance you can find out which "true" Moray Eels inhabit freshwater, brackish, and/or marine environments, and what each of their primary water habitat preferences are.

• View the Freshwater/Brackish/Saltwater Moray Eel Species List

Now, when it comes to the identification of Eels, even trying to identify them by their scientific names can be confusing. With the cross referencing of the Nominal Species and Present Allocation names provided on the fishbase.org's List of Nominal Species of Muraenidae , we found this to be very helpful. Another valuable resource found here is the Synonyms category (located at the bottom of each Eel page under More Information). Click on this and it gives you a list of all the names associated with a particular species, providing a no or yes answer as to their validity. Under the Environment category on some of the Eels you'll also notice the word demersal used. So what the heck does that mean? We didn't know either, so we decided to look it up. It wasn't in our American Heritage Dictionary, nor could we find it on several computer thesauruses. Once again using the fishbase.org Glossary Search, we found it. Demersal: S inking to or lying on the bottom; living on or near the bottom and feeding on benthic organisms. Ok, so what does benthic mean? Found that too. Benthic: Dwelling on, or relating to, the bottom of a body of water; living on the bottom of the ocean and feeding on benthic organisms. Now you know that simply, Eels are bottom-dwelling creatures.

Next Page > Freshwater VS Saltwater Moray Eels - Page 2