Altum versus Scalare angels, how to distinguish them

Hi all of you angel enthusiasists,

We have been seeing all sorts of claims about angels being Pterophyllum altum x Pterophyllum scalare angels, some of which are being called Dantums and so-called "Peruvian altums". None of these are altums and I think everyone is being tricked into thinking that they are buying altums or part bred altums, but none of what I have seen here on the forum lately shows any signs of altum parents, none whatsoever, all are forms of scalare. I think poor SA aquarists are being conned again and again because they just simply don't know the difference. So I am showing what you should be looking for to be able to identify the differences.

In the next two pics, I firstly show a young altum angel which at this size is about the size of an adult scalare angel and I am showing this size specifically so that you can see the differences between altum and scalare at a comparable size. I have indicated various parts that you must watch to be able to keep them apart and I will discuss these after this. Please note this applies to wild type scalare angels in terms of colour, fancy angel strains show different colours.

Young altum angel:




Female adult scalare angel:



These are the differences:

1. the shape of the tail fin: In altums this is concave and in scalare this is convex. The fishes must be fully stretched out vertically to be able to see this and not swimming forward and pinching their tails. Note also that altum do not have barring on the tail fin but scalare angels will have distinct bars.

2. the notch on the forehead. In altums this is a deep notch which is older fishes becomes a lot deeper and more pronounced, in all scalare this notch is a lot less deep and it may not even be there.

3. ventral fins show trailers in both altums and scalare, but altums most of them show only one fin extension, perhaps two. In scalare, males have at least 5-6 trailers or fin extensions, but then this only shows in high quality scalare such as my fishes which are not raised in too great numbers. Often these trailers are nibbled off and you do not see them on adults. In the female scalare that I am showing she also has only two fin extensions, in most female scalare there is also only one fin extension.

4. the pectoral fins in altums are bent forward where I show the top arrow, and where I show the bottom arrow they bend back quite strongly, but just near the tips. In scalare the pectoral fins are bowed back uniformely from top to bottom. When they swim forward these differences are more pronounced, scalare angels let the pectoral fins fold back, whilst altums hold these fins more rigidly straight, altums in general also fold the dorsal and ventral fins back less than scalare.

5. Additional shadow bar between the second and the third black bar: Scalare in most cases don't show an additional bar here, but they can have the starts of a bar but then it is black. In altums they show these shadow bars but they are not black but brown to cream coloured. In general, altums can vary their bars rapidly from jet black to very pale, and normal scalare cannot do this nearly as much.

6. tail fin extensions. P scalare if they are raised under not too high densities will show nice trailers on the bottom and top ray of the tail, but they are never very long. In altums these can be very long sometimes quite the length of the actual tail fin.

After this I will show more pics to illustrate the differences.

Kind regards,

Dirk

 

OK, here are some more pics of altums to emphasize some of the differences that I have mentioned above:



This is one of my own young fishes in 2007.



The same fishes a few moments later now having made their stripes completely pale, note the tail fin extensions.



This is a pic from the finarama forum of an adult altum which must be about 35 cm tall. The body size of this fish is the size of the palm of a large man's hand, so about 10-11 cm. Note that this pic is taken from a slight angle making the fish appear even taller, so don't get the feeling that they are all that narrow. Scalare angels normally don't grow much taller than 22 cm.

Look at all the points that I indicate in the previous post and compare carefully so that you can see the differences.

Will post possible mixes after this.

Kind regards,

Dirk

 

Morning Dirk

Thanks for taking the time out to document this. Could the powers that be make this a sticky please.

Im now dead keen to see the result of the hybrid forms, but doubt anything can come near to a true Altum.

Andrew

 

Just two more pics of genuine altums which I took in June 2011 when I visited Simon Forkel in Germany. His aquaria are either 60 or 70 cm deep. I kept the two batches that I have had before, in 50 cm deep tanks but this has an influence on their fin development, they drag their ventral fins on the bottom of the tank and they are then damaged.

These are altums from the Rio Inirida, a tributary of the Orinoco, and upper Rio Orinoco.



And this is a pair of altum from the Rio Atabapo, another tributary of the Rio Orinoco.



Look at the dark black body markings which can vary according to mood, but the Rio Atabapo fishes are blacker. Look at the bend in the ventrals again. All of this is very different to P scalare. All of these fishes are 35 cm tall, the pair at the bottom are about 40 cm tall.

These sizes are never reached by intermediates or what are claimed to be crosses of altum and scalare.

Kind regards,

Dirk

 

OK, now the first so-called altum that is not an altum, is the so-called Peruvian altum. Just do a little bit of Googling and you will find lots of information indicating that they are not altums Pterophyllum scalare (Angelfish) | Nobobo.com .

One must understand where this originates. Altums occur in the upper Rio Orinoco and in the highest reaches of the Rio Negro which is part of the Amazon, but it does not occur anywhere else in the Amazon. The country of Peru lies in the upper reaches of the Amazon and not near the Orinoco and altums just do not occur there. Many fishes from the Amazon are exported from the city of Laetitia which is a town lying on the Amazon. Have a look on Google Earth. This is an area in which Pterophyllum scalare angels occur. Nice scalare angels were discovered near Laetitia, some had orange dots, others don't have the orange dots, and then as a marketing ploy they were called Peruvian altums. This name has stuck, because it means dealers can sell them as altums which attract a lot more attention. They are easier to keep and so the unknowing public think they are getting altums, but they are not.

However, I find these fishes very attractive and I have nothing against them, but claiming that they are altums or have any altum parentage are false. Why persons claim that they are altums is because they have a strong notch on the nose, but importantly they have convex tail margins which is the deciding character besides a string of other fin ray measurements which ichthyologists measure.

I show two pics of Peruvian P scalare after this:

 

It was all perfectly clear to me when referenced with the pictures so nothing a minor post edit cant fix.

Thanks Prof, that answered many lingering questions I had about my dantum angels.

What I find remarkable is that any other hybrid gets shunned but possible scalare/altum hybrids gets people in a frenzy. Goes to show how well loved angels are to our hobby. I for one am glad there is no confirmed hybrid, I feel that Altums would lose a lot of their mystique if there was.

 

Thanx for the time and effort to make this thread @Dirk may we never see altum X scalare mentiond again.

 

Ok, to follow on here, Dirk is quite correct. If you follow the angle from the tip of the streamers to the edge of the tail fin, it is indeed convex for Altums and concave for scalares.

@Altum, hope this sorts out your confusion.

Kind regards

Andrew

 

I have asked the mods to change the wording on post 1 and post 5 so as not to cause possible confusion. Importantly, I have drawn lines on those first two pics and this brings across the message quite clearly as far as I am concerned.

Eugene, I want to post some more information after this for the reasons for the altum x scalare hybrids and where this story comes from. Ryno, what I want to show is that there is evidence which does show natural hybridization between altum and scalare, but I need to do this properly and show you some maps of the Orinoco and Amazon drainages in South America so that you can understand this. I fear that altum x scalare won't go away, but we do not need further confusion by persons starting names such as Dantums.

However, this will be a mega post and I do not have the time now to do this, so watch this space....

Kind regards,

Dirk

 

Thanks @Dirk, another thread that should be Sticky-ed, stuck, ?????. I will be watching this space!

 

I learnt a lot from this thread, thank you. Very informative.

 

Personally i think some of the strongest evidence that these are not hybrids comes from the fact that these fish breed fairly easily and that most (or a large fraction) of the offspring seem to be viable. Hybrids of most species (as a general rule) are invariably sterile or produce offspring that are not viable>

 

Hi Guys,

I hope to teach you a little more, I must see how much time I have.

Aqii, hybridization in the context that you mention, is actually a topic on its own. I want to make a few comments about this here, but I would like to ask that we do not overwhelm this thread with this discussion. From the knowledge scientists have gained in genetics we now know that hybrids occur far more commonly than what was thought. You say that hybrids are invariably sterile as a general rule or produce offspring are not viable. This idea was developed many years ago because it was observed that if horses and donkeys were crossed, they produced mules which were sterile. The same applies for many other animals as well. However, this applies when animals are distantly related but if they are more closely related they can hybridize and the hybrids certainly are healthy and viable. In plants in general, hybridization occurs commonly, hybrids are not sterile and the offspring are very often fully viable. So to get this back to the topic, in the case of scalare x altum, this is certainly possible. However, I need to explain more before the message can across clearly, so I will explain soon.

Kind regards,

Dirk

 

What about the albino scalare? What is the story behind them prof?

 

Thank you Professor. I was always taught that globally post-zygotic isolation barriers were very effective at severely limiting inter-species hybridization (and not only in equines)....taught wrong, eish !! But, agree, not to sidetrack the discussion also very much look forward to your analysis

 

Thanks for the informative thread, Professor!

I actually bought 6 juvenile Dantum angels yesterday for my 200L planted tank. I must say that I really prefer them to the odd strains we are seeing in the trade at the moment. They just look far more natural. One day, when I am big, I will have a school of true Altums in an aquarium.

 

Hi Hennie,

Albino scalare a mutation of wild type scalare, just as a whole host of different forms are: black, marble, halfblack, goldens, koi, ghosts and so we can carry on. But again, we should discuss these in a different thread, but one at a time please! First the scalare x altum story.......

Kind regards,

Dirk

 

Hi Sean,

Could you please do us a favor and take some nice pics of these fishes when they have settled in so that we can see what we are dealing with here.

Many thanks,

Dirk

 

I will do! They are quite small still. Their bodies are about the size of a R5 coin at the moment.

 

I also purchased the same guys @Sean J and @Dirk including the albinos, they where sold as Albino ALtum (Dantum) and Altum surnium red spot.