# Other Aquarium Forums > Freshwater Fauna > Cyprinids >  B. hexazona a strain of B. pentazona?

## XnSdVd

Would the gurus answer this question for me? I've seen several books where hexazona is called pentazona. And I'm pretty sure they're hexazona. 1st stripe at the tail, last stripe down the eye. No breaks along the stripes. 

So, What does this mean they're the same species but of different strains? or are the strains different enough to warrant it's own species? Also, spoke to michael lee from MAD Tanks. He says the 5 banded strain is found in johor. The 6 banded strain is singaporean. 

But since they've been seperated from each other for the last god knows how many hundered thousand years. There should be a distinct genetic difference. ESPECIALLY because there's an extra band... pentazona lacks the tail stripe.

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## stormhawk

They are distinct species in their own right. Not a strain of either.

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## XnSdVd

Darn the books! Darn them all to heck! 

Ok, seriously dude, are you sure? I can't imagine how they'd let a huge print error like that get through...

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## hwchoy

what do you mean? they all have the same bands, except pentazona has a blotch under the dorsal fin which is lacking in hexazona.

also hexazona appears to range throughout Malaya (including Singapore) and Kalimantan/Borneo (I think north of Kuching) while Pentazona ranges throughout Malaya and Sumatra (but not recorded from Singapore) and also in Kalimantan/Borneo (but not overlapping in range with hexazona).

don't believe anything BOOKS says, unless it is a scientific paper. even then, this group of fishes are poorly studied. I have personally seen population where the dorsal spot varies in size from big to almost non-existence.

also hexazona from Singapore, and those from Pontian are quite different looking, yet similar to those from Tj Malim.

you got a pix of your pentazona? not sure what you mean by "extra band"

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## hwchoy

> Darn the books! Darn them all to heck! 
> 
> Ok, seriously dude, are you sure? I can't imagine how they'd let a huge print error like that get through...



not a print error, just ignorance or perhaps lack of definitive information. what? you think these books are written by scientists? even scientists make mistakes  :Smile:

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## stormhawk

Choy, post up the images of both pentazona and hexazona for comparison lah.  :Smile:

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## hwchoy

btw where you get the "B." from? It is either "P." for _Puntius_ or _S._ for _Systomus_ (depending which school of thought you prefer to follow).

if those books uses "B." as in _Barbus_, well, you should dump them down the chutes  :Smile:

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## hwchoy

pardon the pix quality, these are rather old pix and not very well taken.
OK, this is a _Systomus hexazona_ wild-caught in Singapore (ignore the label on the photo, it is WRONG!)





and this is a _Systomus pentazona_

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## XnSdVd

Stupid book... Thanks for the explaination choy  :Smile:  The pic in the book showed something like a cross between the two. Essentially it looked like a pentazona without the blotch. 

Also, the body structure of hexazona looks very different from the ones i used to have. Does this vary from region to region? Or is the pic in your post of a young fish?

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## stormhawk

The body form slightly varies amongst the hexazona populations. I still have a few healthy ones in my 2ft tank and they're huge! Too much worms I think.  :Grin: 
Anyway these were said to be Malaysian in origin so I won't be surprised if they're of the Johore population.

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## hwchoy

my single specimen just died unexpectedly  :Sad:  this is the one from Pontian which is more glittery but less red, and seem to be larger in size.

the Singapore ones I had, and those I have seen attributed to Tj Malim, are smaller, redder and less glittery.

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## stormhawk

Choy, those I bought from an LFS at Bt Timah Plaza some time back turned very glittery in the black bands and are of an intense orange-red colour in my tank. I found a contaminant piece in a batch of rhomboocellatus from CS and that fella isn't glittery. The rhombos that I brought back are still very glittery though.  :Grin:

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## hwchoy

maybe I should clarify, it is not that the glittery ones (and these seem to be bigger and deeper bodied) are not red, they are red in a different way from the non-glittery ones. I don't think they are male/female forms either because both forms has individuals with red or clear fins which I assume to be sexual dimorphism.

do you see the same characteristics with yours, _stormhawki_?

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## XnSdVd

But how much does body structure vary within the singaporean population? That and since you brought it up. Why is it most books refer to them as Barbus? Oh and Is Boraras the proper genus for rasboras? And would you mind explaining the difference between puntius and systomus? And is johorensis a seperate species or the old name?

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## Justikanz

That's all history... Books are not as updated... If you read the books and mags, you will slowly be bathed in the history of the ichthyology... Picking things up along the way...

If I did not recall wrongly:

Most, if not all, barbs start with Barbus, then some ichthyologists developed the genus Punitus etc to classify the fish better within the family. Same thing with the Rasboras, the Boraras genus name is relatively new and is reserved for the smaller rasboras now known as the Boraras...

Same thing with chichlids, but they are more confusing. Simpler ones like how Apistogramma ramirezi (Ram) becomes Papilochromis ramirezi, then becomes Mic(k)rogeophagus ramirezi... Confusing ones like how a lot of the larger cichlids used to be Cichlasoma spp.. Then they were split to more dedicated Heros, Thorichthys, Vieja etc...

Choy, ok?  :Smile:

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## XnSdVd

:Shocked:  
 :Huh?:  
 :Knockout:

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## Justikanz

It comes with ease as you read... The key is to read, read and read... And books are definitely outdated. Magazines are more updated but the best are the journals for ichthyology...

Oh, btw, those I mentioned are just a tip of the iceberg...  :Grin:

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## XnSdVd

But where would I find these books? All I have is that one by BP and the science centre...

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## Justikanz

Books ah? Everywhere lah... Bookstores lor... Can grab some stuff from Kino, Times, MPH or even from some LFS... Good to have the Axelrod's Atlas, but be warned, it is expensive and they need regular updating... Now it is at Version 10 liao wor...  :Smile: 

It is always good to have at least 1 on hand... I have at least 17 books on fish, plants and scapes...

Oh, and some can look very simple, like pictorial books, but they might woth buying... Oh, avoid lousy books such as the 'Du**ies' series... I always look out for simple info to check if the book is worth buying. I had seen 1 that state clownfish are freshwater fish...

Get the newest edition, use Boraras as a guide, for example. 

Happy book shopping...  :Smile:

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## hwchoy

> But how much does body structure vary within the singaporean population? That and since you brought it up. Why is it most books refer to them as Barbus? Oh and Is Boraras the proper genus for rasboras? And would you mind explaining the difference between puntius and systomus? And is johorensis a seperate species or the old name?



from what I have seen there appears to be two main forms of hexazona.

_Barbus_ generally refers to members in Europe and Africa, while _Puntius_ is applied to Asian species. Both genera are probably not monophyletic (meaning they should be split into smaller groupings to reveal the inter-relatedness of their members).

Similarly with _Rasbora_, some members has been taken out and assigned to new genus, for example:
the group of small fishes now assigned to _Boraras_a single species of small fish now assigned to _Sundadanio axelrodi_the group of fishes containing the Harlequin Rasbora, now assigned to _Trigonostigma_

as I have said, read scientific description papers, rather than books. the papers are the definitive (although still open to debate and arguments  :Smile:  ) sources.

you can start from here http://rmbr.nus.edu.sg/rbz/biblio/#1
BTW you need to edit your signature, the harlequin is _Trigonostigma heteromorpha_  :Sad:

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## hwchoy

> That's all history... Books are not as updated...



you'd be surprised how little some authors know! the key is read selectively  :Angel:

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## hwchoy

> But where would I find these books? All I have is that one by BP and the science centre...



that book is written by scientists, very good except for one little mistake regarding the hexazona/johorensis. when I find some time I will tell the story  :Smile:

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## hwchoy

> then some ichthyologists developed the genus Punitus




when scientists says "erection" do not blush. what they meant is "creating" a new taxonomy classification such as a new genus. so in their parlance you would say: "then some ichthyologists erected the genus _Puntius_"  :Laughing:

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## hwchoy

> But how much does body structure vary within the singaporean population? That and since you brought it up. Why is it most books refer to them as Barbus? Oh and Is Boraras the proper genus for rasboras? And would you mind explaining the difference between puntius and systomus? And is johorensis a seperate species or the old name?


johorensis is a different fish from hexazona, the scientists made a mistake  :Smile: 

here I reproduce what Ng Heok Hee (a Singapore scientist now at Michigan studying for his PhD) said about _Systomus_ and also the confusion of johorensis and hexazona:


First the issue of _Systomus_ vs. _Puntius_. Systomus was resurrected as a valid genus by Walter Rainboth, who used it for small barbs with a serrated dorsal-fin spine, 2 or 4 barbels, and less than 12 gill rakers on the first gill arch. In contrast, _Puntius_ would have a smooth dorsal spine, only 2 (never 4) barbels, and more than 12 gill rakers on the first arch. So, by this definition, many of the barbs encountered in the aquarium trade are _Systomus_ (_S. tetrazona_, _S. binotatus_, _S. hexazona_, _S. partipentazona_, _S. johorensis_, _S. gemellus_, and so on...).

Of course, this scheme is not adhered to by all workers, so some references (notably those of Kottelat) still refer to these as _Puntius_.

Next, the identity of the six-banded barb. The correct name should be _S. hexazona_. The six-banded barb has long been misidentified as _Systomus (Puntius) johorensis_. However, the name _S. johorensis_ actually applies to the barb that is commonly identified as _Systomus (Puntius) eugrammus_ (the striped barb), a much larger species. Part of the confusion lies in the fact that young _S. johorensis_ have a barred pattern very similar to that of the six-banded barb (the vertical bars break up with age and become horizontal stripes instead).

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## XnSdVd

Woah... thanks for the info choy  :Smile: 
Have you ever thought of writing a book yourself? Considering you seem more up to date than most of the authors whose works are being published...

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## hwchoy

> Woah... thanks for the info choy 
> Have you ever thought of writing a book yourself? Considering you seem more up to date than most of the authors whose works are being published...



write book!  :Confused:  I know what I don't know, hence I don't  :Roll Eyes:  

eh, your signature mispelt _Trigonostigma_ liaoz  :Blah:

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## hwchoy

btw here's what a _Systomus johorensis_ should look like

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