A Lesson on Flounders/Soles and Using common Names.
Posted: Tue Aug 15, 2006 6:14 pm
Ok guys here is the "dish", there are many genus of flat fish which are called by the common name flounder. These animals while having similar biology come from many different type of niches, including freshwater rivers to temperate marine environments. Uttering a statement about general care on flounders/soles/flatfish like, “All Flounders thrive in ‘X’ environment” is just about as ignorant, not knowing, as the statement, “All Puffers thrive in ‘X’ environment.” We know that puffers, come from multiple different niches and that individual species have to be identified to determine proper care, the same is true of flounders and soles;
***Some are strictly freshwater, very few...not commonly seen specimens
***Some are strictly Marine
***Some are Brackish
***Some start there lives in freshwater and as they mature end up living in marine niches
…Since each species is different it MUST be positively identified before purchase (NOT AFTER!). If you cannot do this, then you cannot provide the proper care for this animal.
As I mentioned before many fish bear the common name flounder…some are soles (not even in the flounder family) let’s discuss the animals commonly seen in, captivity and there care. Those that are both appropriate and inappropriate:
Robert Fenner, “About Freshwater "Flounders" of the Families Achiridae, Soleidae, Cynoglossidae, Pleuronectidae. Yes, there are maybe four true freshwater Flatfishes, though strictly speaking they are not true "flounders", as well as many brackish species that venture upriver temporarily.”
The most common animals sold as Flounder to us aquarists is not actually a flounder but a Sole, those that belong to the genus Achiridae. A list below includes some that are commonly sold as “Freshwater Soles”…though mind you not all belong in freshwater;
***Not a complete list, but rather what “you guys” will more than likely see…
Achirus achirus, the Drab Sole
To 7” in length, this is the most common sole seen for sale in American Shops. It is deciveingly sold as a purely freshwater animal though larger adults 4”+ will thrive and live much longer in a slightly brackish environment. 1.0005 to 1.0016. They are very prone to bacterial infections from coarse substrate often used by aquarists.
Achirus lineatus, Lined Sole
This animal hails from the gulf of Mexico and while it commonly ventures into FW for very abbreviated periods of time, it belongs in high brackish environment, eventually marine!!! To 9” in legnth.
Achiropsis nattereri, S.A. Freshwater Sole
The only purely freshwater animal in this genus, however it reaches 10” as an adult
More Soles;
Aserragodes therese, Therese’s Sole/Hawaiin Sole
To only 3” in legnth, is born in and requires a full marine environment
Genus Cynoglossidae, the Tongue Fish
Encounterred worldwide in many boddies of water (topical and sub-tropical), does venture into freshwater but most species of the genus will live stunted lives if not given high brackish or full marine environments as adults, 4”+ in legnth.
Genus Pleuronectidae, (P. Ritteri)
VERY, VERY RARELY is encounterred in freshwater streams though it has been reported, mostly encounterred in Baja California. Requres a full marine environment and reaches 16” in legnth.
****I, in all my research and experience, have not encounterred a true freshwater flounder that demands the care level and reaches the size that has been posted in this thread. Apparently neither has Robert Fenner. If you know of such an animal, and have it’s exact species name, please educate us.*******
Adam J
***Some are strictly freshwater, very few...not commonly seen specimens
***Some are strictly Marine
***Some are Brackish
***Some start there lives in freshwater and as they mature end up living in marine niches
…Since each species is different it MUST be positively identified before purchase (NOT AFTER!). If you cannot do this, then you cannot provide the proper care for this animal.
As I mentioned before many fish bear the common name flounder…some are soles (not even in the flounder family) let’s discuss the animals commonly seen in, captivity and there care. Those that are both appropriate and inappropriate:
Robert Fenner, “About Freshwater "Flounders" of the Families Achiridae, Soleidae, Cynoglossidae, Pleuronectidae. Yes, there are maybe four true freshwater Flatfishes, though strictly speaking they are not true "flounders", as well as many brackish species that venture upriver temporarily.”
The most common animals sold as Flounder to us aquarists is not actually a flounder but a Sole, those that belong to the genus Achiridae. A list below includes some that are commonly sold as “Freshwater Soles”…though mind you not all belong in freshwater;
***Not a complete list, but rather what “you guys” will more than likely see…
Achirus achirus, the Drab Sole
To 7” in length, this is the most common sole seen for sale in American Shops. It is deciveingly sold as a purely freshwater animal though larger adults 4”+ will thrive and live much longer in a slightly brackish environment. 1.0005 to 1.0016. They are very prone to bacterial infections from coarse substrate often used by aquarists.
Achirus lineatus, Lined Sole
This animal hails from the gulf of Mexico and while it commonly ventures into FW for very abbreviated periods of time, it belongs in high brackish environment, eventually marine!!! To 9” in legnth.
Achiropsis nattereri, S.A. Freshwater Sole
The only purely freshwater animal in this genus, however it reaches 10” as an adult
More Soles;
Aserragodes therese, Therese’s Sole/Hawaiin Sole
To only 3” in legnth, is born in and requires a full marine environment
Genus Cynoglossidae, the Tongue Fish
Encounterred worldwide in many boddies of water (topical and sub-tropical), does venture into freshwater but most species of the genus will live stunted lives if not given high brackish or full marine environments as adults, 4”+ in legnth.
Genus Pleuronectidae, (P. Ritteri)
VERY, VERY RARELY is encounterred in freshwater streams though it has been reported, mostly encounterred in Baja California. Requres a full marine environment and reaches 16” in legnth.
****I, in all my research and experience, have not encounterred a true freshwater flounder that demands the care level and reaches the size that has been posted in this thread. Apparently neither has Robert Fenner. If you know of such an animal, and have it’s exact species name, please educate us.*******
Adam J
