Identify this bicher?

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think regardless of species, it does behave like a delhezi...

What still buffles me is that it has grown from 12" to 14" in the past 2 months... pretty heavy eater...

If it is a del, it should be at its max size now... but it doesn't seem want to stop growing... is there any cases where Dels outgrow 16" ?

Thanks everyone for contributing anyway.. ;)
 
Hey Vince,

that's a nice pic... retropinnis looks more like Ornate than a Delhezi, esp its finnage and colourage...

Did saw a few in my lfs last week... small babies... thought they were cross-breed of palmas and ornate.. lol :D
 
Sorry to sidetrack the thread slightly but does anyone know much about polypterus sp congo or zaire green.Looks much like a weeksii variant?
 
Vince said:
This is a retropinnis.

I resized the pictures for better and clarifying view.
P. Palmas "Zaire Green" is an offshoot of the polli that has green markings. Whereas the P. weeksii has stripes like the normal delhizi, with a much larger head.

Here is my ornate at 18".

HPIM1718.jpg
 
To those still tossing the identification of this bichir around based on its coloration and pattern I offer this:

Coloration and pattern are unreliable characters on which to base species (or even subspecies) identification. Both of those characters are quite variable on an individual level and can even change significantly in a single individual over time.

More reliable characters for identification in Polypterids are things like number of dorsal finlets (which is practically always a range of numbers rather than a specific number), number of predorsal scales (which generally determines the distance from the end of the head 'plates' and the first dorsal finlet), etc.

Simply put, you cannot make a reliable diagnosis of the species (or subspecies) of a bichir on the basis of its color pattern alone, though that can often be a valuable clue. You have to take the extra steps of doing some scale counts and fin counts to solve some of the more problemmatic identifications.

The fish in question here does not appear to have the characteristics that would make it Polypterus ornatipinnis, regardless of its pattern. Obviously, to make a definitive diagnosis would require being able to do accurate counts but, on the basis of what I can see in the pictures, I still maintain that this is an aberrantly-colored Polypterus delhezi. Oh.....green coloration in the fins does not a Polypterus palmas complex fish make!

-Joe
 
Clare.....

On your sidetrack.....Polypterus sp. 'Congo' (also called the 'Zaire Green') is definitely a problemmatical fish. It shares with Polypterus retropinnis a large number of predorsal scales, which means that its first dorsal finlet originates relatively far back on its body. The body coloration and pattern seems to be highly variable. Whether it is actually a member of the Polypterus palmas complex in the strictest sense is debatable. Frank Schafer (author of the Aqualog Polypterus book) told me in personal communication that he is currently working on a scientific description of the 'Zaire Green'. Hopefully something will be published relatively soon, though he is a busy man.

In the meantime, I've included a picture of my Polypterus sp. 'Congo' below. You can easily make out the very long relative distance between the end of the head region and the origin of the first dorsal finlet.

-Joe

punkn3as.jpg
 
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