Corey hybrid: Panda + Julii/Trilineatus

[Joel Espinoza]

A few years ago I bought 3 of each Panda and what I was told were Julii Coreys, but are more likely Trilineatus, these are the only Coreys I have ever put in my community tank. The Pandas have had some success with offspring and I think there are 5-6 of them now, but a while back I spotted a Corey that clearly wasnt the same as either species. I assume he must be a hybrid of the two.

[bekateen]

Hi Joel,

First, welcome to PlanetCatfish.

Now, regarding your question, I don't wish to be skeptical or rude, but I have questions. Before you read them, please understand that although they may sound rude, I don't mean them to be so - I just want to cover all the bases and rule out possible explanations.

• You say that you discovered this fish "a while back." What does that mean? Are you saying that when you finally discovered it, it was about the size that it is in your photo? Did you not see this fish grow up from a small fry to this size, with various ages/sizes and the same color pattern in between? How big and how crowded is this community tank where these fish live? How difficult is it for you to see the corys on a regular basis?
• If the answer to the first question is that you found this fish like this (about this size and its color fully developed), then my next question sounds worse (sorry): Are you 100% confident that this fish is one of the offspring from your original six fish? In your first photo, it looks about as large as your panda, so I'm wondering if it could have been one of the original six and its color difference is just becoming obvious to you now.
• Do you still have your original three trilineatus, and can you identify your original three pandas? (presumably, you can tell them apart from the 2-3 offspring you've raised)
• Finally, is there ANY chance that someone else placed this fish in your aquarium without your knowing? (If you know you didn't buy this fish, and you never saw it grow up, this would be my choice).

Honestly, your fish looks very similar to a normal

Corydoras paleatus

(or something like it: your fish does appear to have a strong dark line along the dorsal spine and first dorsal rays, which is more prominent than what I'm used to seeing in paleatus; this is the principle reason why I'm open to the idea of a hybrid in your case, but I have reservations). Although I have no idea what a hybrid between a

Corydoras panda

and

Corydoras trilineatus

would look like, I must admit that I would be surprised to discover that it looks like a paleatus (except see my comment above).

Finally,

• If you want to know more about pandas hybridizing (which I've read before they like to do) or trilineatus hybridizing, I recommend you run searchs of the forums here using the keywords panda hybrid (here), panda cross breed (here), trilineatus hybrid (here), and trilineatus cross breed (here).
• You might be particularly interested in a thread about panda X paleatus hybrids: http://www.planetcatfish.com/forum/view ... =6&t=27029.
• There is also at least one specific thread about panda x trilineatus (http://www.planetcatfish.com/forum/view ... =6&t=39477) but it has no photos and therefore won't offer you the confirmation you'd like.
• This might also be helpful: http://www.planetcatfish.com/forum/view ... f=6&t=6394.
• One more thing: Elsewhere in the forum is a thread (here) that includes a list of known Corydoras interspecific hybrids.

Cheers, Eric

[bekateen]

Admin, can this please be moved to the "South American Catfishes (Callichthyidae - Corys et al)" forum? Thank you.

[Birger]

Admin, can this please be moved to the "South American Catfishes (Callichthyidae - Corys et al)" forum? Thank you.

Done

[bekateen]

Thanks, Birger.

[Karsten S.]

Hi,

Eric is absolutely right with his comments.
I have already seen hybrids of C. panda and C. trilineatus and they look completely different. Just add a faded caudal blotch of C. panda to a C. trilineatus and then you know how they look like.

In all cases of Corydoras hybrids that I know you can rather clearly recognize the parents.
I have never seen some pattern (like a dark bar in the dorsal fin) appearing in hybrids that the parents don't have.

One possibility could also be that a C. paleatus egg on a plant was added to the tank.

Cheers,

[Joel Espinoza]

You say that you discovered this fish "a while back." What does that mean? Are you saying that when you finally discovered it, it was about the size that it is in your photo? Did you not see this fish grow up from a small fry to this size, with various ages/sizes and the same color pattern in between? How big and how crowded is this community tank where these fish live? How difficult is it for you to see the corys on a regular basis?

The tank is very crowded, and until recently I had a LOT of java fern in there. I took out a 5 gallon bucket PACKED with java fern and not long after that I noticed him. He was slightly smaller then the oldest adult pandas then, now he is slightly larger than them, but smaller than the Julii/Trilineatus.

I often miss fish in the tank, I was looking at it earlier this week and was worried that several of my black neon tetras looked quite pale, and were missing most of their distinct black line. Then I realized all the pale ones were slightly smaller, and that I had about 15 of them, since I had originally only bought 6, I assume they bred at some point. The Juvenile Panda coreys I didnt see until they were about 1/3rd the length of the adults and were out foraging with their parrents. They were VERY obviously little minature panda coreys, but I just hadnt seen them before that.

If the answer to the first question is that you found this fish like this (about this size and its color fully developed), then my next question sounds worse (sorry): Are you 100% confident that this fish is one of the offspring from your original six fish? In your first photo, it looks about as large as your panda, so I'm wondering if it could have been one of the original six and its color difference is just becoming obvious to you now.

There have only ever been these 2 species of Cory in there, and they were very distinctly identifiable when I bought them, there isnt any way I could have confused him with either of the other 2 species. When I got these guys my tank was VERY sparsely planted and there really was no way I could have confused their very distinct patterns as I would often watch all 6 of them forage for food.

Do you still have your original three trilineatus, and can you identify your original three pandas? (presumably, you can tell them apart from the 2-3 offspring you've raised)

I have seen 2 of the trilineatus, I havent dug around looking for the 3rd. It isnt impossible he could have died or even been removed and sent to my friends pond when I took out the masses of Java fern. There are around 6 Pandas in there, and they are all close to the same size, the first batch I saw as juveniles were at least a year ago, and they are full grown now.

Finally, is there ANY chance that someone else placed this fish in your aquarium without your knowing? (If you know you didn't buy this fish, and you never saw it grow up, this would be my choice).

No, there is absoutely zero chance of that. No one is around my tank when I am not there except my wife, and she has never bought fish wihout me. I just asked her to double check.

The egg on a plant theory isnt impossible, but this guy has grown noticiably in the last month since I first saw him, so I expect he isnt that old. The most recent plant additions to that tank were at least 2 years ago, and they were sealed petsmart plants, and I would be very surprised if they had a viable Cory egg on them with them packaged mostly dry.

[bekateen]

Hi Joel,

Thanks for the thorough answers; they are specific and exhaustive (except for your most recent observation of only two trilineatus at once, which leaves open a small window of doubt). Otherwise, what you've written above leaves little room for any other explanation than this mystery fish is a panda x trilineatus hybrid. While I can accept the possibility, I can't tell you how true (in my limited exposure to photos of other people's cory hybrids) Karsten's statement tends to be:

In all cases of Corydoras hybrids that I know you can rather clearly recognize the parents.
I have never seen some pattern (like a dark bar in the dorsal fin) appearing in hybrids that the parents don't have. (comment by Eric: Okay, but in consideration of your mystery fish, the panda x paleatus hybrid shown in the link below does appear to have a dark bar on the dorsal fin, which is not like the totally black dorsal of panda or mottled dorsal of paleatus)

That's why I referred you to the thread showing the results of a panda x paleatus cross, as this hybrid clearly shows a blended parent coloration pattern. You can also see this in the two examples of cory hybrids shown in the Corydoras pages:

Corydoras sp_hybrid(1)

and

Corydoras sp_hybrid(2)

. Also, I found several photos of actual panda x trilineatus hybrids here (from there, click on the "sp. Hybrid" link in the left side column of links; a list of various cory hybrids will appear - I'm displaying two of the panda x trilineatus pics below):


But if you are confident of the following details:

• This CANNOT be one of your original purchased corys (as long as you can find your third trilineatus);
• NOBODY could have placed a fish in your tank; and
• You haven't purchased any plants for a long time (what about other non-plant decorations that might have been placed into your tank from other pre-existing aquaria? Have you traded anything lately?);

then I am at a loss to explain this fish other than to consider the possibility that it is a hybrid.

Still I find it very odd that this fish, the fruit of a panda x trilineatus cross, would look so much like another pre-existing species (a paleatus-like cory).

Good luck with your fish, and keep us updated! And please, out of respect for the parent species, do not release this fish to other people who might breed the fish (if it is a hybrid) and spread them around.

Cheers, Eric

P.S., If you have more than one aquarium, my advice would be to remove this mystery cory to a different tank, to prevent it from crossing back with the parents (in the event this is a hybrid); and if you have another tank, I'd suggest separating the trilineatus and pandas too, to avoid potential hybridization in the future.

P.P.S.

He was slightly smaller then the oldest adult pandas then, now he is slightly larger than them, but smaller than the Julii/Trilineatus.

Full-grown paleatus are larger than both pandas and trilineatus. The fact that your fish is growing so fast indicates that it is not yet full grown.

[Joel Espinoza]

He is DEFINATELY not one of my original 6 Pandas or Trilineatus, I have some pictures of them from Aug of 2011, when my tank was mostly empty, sadly none of the pics show all 6, but I can tell you that I looked at them a lot back then and could easily identify 3 of each species.

I havent traded any plants or decorations of any kind for over a year, I can ask that guy if he kept any corys in that tank I got the plants from. Other than that the last plants I got were years prior to that, around 2012, and they were shipped mostly dry from a seller on ebay.

What you say about size is interesting, it looks like trilineatus and pandas are mostly listed as being the same adult size, however all my trilineatus are substantially larger than all my pandas and have been for years.

I rarely trade any fish other than endlers/guppy hybrids, that I give away all the time. So no worry about me spreading the corys.

[Joel Espinoza]

Until recently there was 4-5x this amount of Java fern in the tank. Enough so that apparently tetras could breed in there even with a ~120w shop light.

I havent seen my vampire shrimp for nearly a year, and he came scooting out when I picked up some wood looking for the cory. That ninja is about 4.5" now.

It is easy to loose track of fish in my tank.

[bekateen]

Hi Joel,

Thanks for the extra info. I have to be honest: While your details leave little room for any interpretation other than hybrid, I'm having a hard time looking at the pics of this fish and seeing anything other than a normal paleatus with a dark band on the dorsal fin. Although that's not the typical appearance of paleatus, it's not unheard of: I've done some more searching and found other photos of paleatus with similar dark bands (e.g., here and here). Granted, you can't always trust photos of corys on the internet to be properly ID'd, so maybe these examples aren't actually paleatus but represent a similar species; but if so many photos of these fish exist, then it's virtually impossible that they are all panda x trilineatus hybrids, without someone reporting them as such, rather than ID'ing them as paleatus.

You may never know what that fish is, but no matter - it's still yours and it's still a nice fish. Take care of it and enjoy it.

Cheers, Eric

[Joel Espinoza]

Yea, I have to assume it is a hybrid, I asked the guy who gave me the plants a year ago, he said he never kept any fish in that tank, and definately not any corys. So it is either a hybrid or the eggs learned to fly.

It seems to do just fine in there nosing around and foraging with my other 2 species and I am sure it will continue to do so. When some of the java fern cover regrows I might even get some more babies.

[Karsten S.]

Hi,

would it be possible to post a better/clearer pic of the cory ?
I still cannot believe that this can be a hybrid of C. panda and C. trilineatus/julii although there seems to be no other possible explanation.

Cheers,

[Joel Espinoza]

Clearer than the second picture? Did you click on it to get the large size?

[Karsten S.]

Hi,

yes, but it's only getting bigger and not sharper .

Even though your explanation doesn't disclose this option I'm still sure that this is neither C. panda or C. trilineatus/julii nor a hybrid of those species.

1. The pattern doesn't match. I don't see much of the typical patterns of both species. I have seen quite a few cory hybrids (on pics) and always the pattern was a blend of both species involved in the hybridisation and never showed a pattern that the parental species don't have.
The picture is rather flat and blurred, a better one might help to see details of the pattern (if it's not the fish itself that looks washed-out as if not feeling good).

2. The form of the dorsal fin doesn't (and other morphometric traits seem not to) match, it is too long and pointed for both species and I again assume that a hybrid would be close to or between the parents. But it does match to C. paleatus.

3. Know hybrids between C. panda and C. trilineatus look completely different (see pics Eric posted).

With genetics nearly everything is possible as we don't know many alleles are involved and what kind of inheritance these have.
But no matter if it is co-dominant or incomplete dominant (based on a certainly limited knowledge of genetics) I would assume that this inheritance behaves always same and you never get completely new traits.

Cheers,

[VelcroWY]

Fascinating discussion - I think "size" is a key word here - if it keeps growing until it's larger than either of the original sets, then it can't be a hybrid. I've never thought about importing a fish egg on a plant before. That would be something rather unusual. Some good advice in here. Perhaps only some more time will tell.

BTW, I have a heavily planted 125g that it is hard to find my fish and I've had some live-bearers "suddenly appear" at a surprising size (but their parents are in the tank, so not shocking). I think my Serpae tetras keep the baby population down though. LOL