C. Fowleri vs C. Apurensis

[moe214]

Just curious. What're the differences between these two fish as far as IDing goes, and then general information such as temperament, Max size etc. I've tried to do some research but get conflicting or unclear info, and they are interesting catfish and I'd like to add to my knowledge. Any experience and information that can be shared anyone? Pictures very welcomed!

 

[Yellowcat]

Firstly I'd suggest looking them up on PlanetCatfish, look them up by species in the Cat-eLog and then there are detailed articles in "Shane's World" on the 3 most kept cephalosilurus species of the 4 that exist, among other links to these fish found there.
Very briefly, c. apurensis are the most common in the hobby, they come from several river systems in Venezuela and possibly Colombia as well. C. Fowleri exist in only one river in Brazil and are much rarer, I haven't seen a 'real' c. fowleri for sale in years. As far as I.D. generally, fowleri tend to be a little more orange in background color, have few if any belly markings compared to apurensis with distinctly marked undersides. Fowleri also have flatter heads and a more squarish tail compared to the more rounded of apurensis and remain less 'girthy' than apurensis as well as only reaching around 18" in length. Apurensis grow faster and larger, to around 28" but it takes several years. Both species can be territorial, aggressive predators, the fowleri only slightly less so, be warned, either species is best kept alone. There are two other cephalosilirus species, c. nigricaudus (look like apurensis with a black tail-rarely imported) from Guyana and Surinam and the rarest, the c . albomarginatus from Guyana-top of my wish list, never seen one imported...

 

[thebiggerthebetter]

page 2, post 17 http://www.monsterfishkeepers.com/forums/threads/my-favorite-cats.664643/page-2#post-7474670

Whatever I know, I know from people like Kirk and Wolfgang Ros. So, I've nothing of value to add on top of their accounts.

Unless I am simply unaware, I hope Kirk one day will do a write-up on his Cephalosilurus and other Pseudopimelodidae adventures.

Wolfgang's articles in German, can google-translate: http://translate.google.com/translate?client=tmpg&hl=en&u=http://www.catfish-and-more.com/berichte/bericht-schwarz-geheimnisvoll-faszinierend-hemibagrus-wyckii/&langpair=de|en

One must also note that, AFAIK, there is no agreement between experts on the Cephalosilurus IDs between apurensis and nigricaudus. IIRC, Kirk and Wolfgang's views were somewhat conflicted on my three big guys from the past. Kirk may kindly offer his views again, if he wills, but Wolfgang is hard to reach (still he is reachable). He gave me his IDs on a former rival site Water Wolves but the site folded and I have stupidly not saved his input.

I am, for one, often confused perhaps in part because of the mood-induced appearance changes that were so well shown by Kirk in the first link in this post.



These guys I've lost on a NY to FL move. I've been growing out another three 1', 10" and 8" currently. Got them from three vastly different places / vendors but the appearance of these seems the same:



I have this photo labeled "Fowleri, juvi" I don't remember the origin of. I think it came from the research done by V victor448 who was looking earnestly into fowleri and has an adult apurensis (Jeff, your input and pics would be great):



HTH.

 

[moe214]

Thank you guys, I see the differences in the pictures of the two species now, I did not pick up on much other than difference in coloration and the fact that the fowleri seemed thinner but I thought that could just be a case of difference in size or maturity. That last pic you posted looks interesting TBTB, it's tail isn't squared, I'd think they'd have developed it by that size seeing as it's developed its colors.

 

[thebiggerthebetter]

I think the bands seen in the fowleri juvi pic are not seen in adults, so this is still baby coloration.

Not that I know that the colors and the fin shape should develop at the same time. I don't know.

 

[jowens]

I'm curious as to the last time anyone has seen a fowleri for sale?

 

[moe214]

I'm curious as to the last time anyone has seen a fowleri for sale?

+1 I've been reading a fair majority of my day about them

 

[victor448]

I have nothing to add to Yellowcats criteria for distinguishing Fowleri from Apurensis.My experience has been with Apurensis. I have not seen Fowleri for sale for at least 10 yrs in the USA ,although several dealers have said they thought they had Fowleri but it turned out to be Apurensis. As Yellow cat also says these fish are best kept alone. I tried two together once and one attacked the other. Although the victim completely healed. These are tough fish.Although they benefit from large weekly water changes and excellent filtration as they have a propensity for giving off more solid waste then you would expect from the amount or type of food given.They are gaping mouths which compensates for its very small eyes with a body attached that lay around motionless a lot of the time unless they sense food is being offered and then they come to the surface slowly then aggressively swallowing what drops into the tank with a loud popping sound of their jaws slamming shut.This has been consistent in adults and juveniles. They seem to prefer being in a cave but also appear unperturbed by having nothing in the aquarium.They are ambush predators that probably avoid other types of engagement in the wild do to their soft skulls and slow speed.Because of a sedentary existence they don't need a large tank or a lot of food,but will almost always take it if offered. As documented elsewhere they can sleep on their backs or face down in a corner as well as in the usual fashion to the point you might think the fish is dead. Maybe this is done to lure prey to its mouth. I find these fish worth the tank space and time to maintain them and would love a Fowleri for comparison.

 

[thebiggerthebetter]

Neither have I seen a fowleri for sale. As Victor448 points out above, a few offered "fowleri" that I came across over years turned out to be apurensis / nigricaudus (because I cannot tell these two apart).

 

[moe214]

Neither have I seen a fowleri for sale. As Victor448 points out above, a few offered "fowleri" that I came across over years turned out to be apurensis / nigricaudus (because I cannot tell these two apart).

How big is nigricaudus supposed to get?