FishProfiles.com Message Forums

I was at another LFS today than the one I work at (shhh...), and in one of the tanks that was seemingly empty, something caught my eye. I took a closer look, and there were two tiny tetras hiding inside the only ornament/decoration in their tank. Then one of them dashed out of the ornament to grab a small drifting particle. I immediately realized that I had never seen this kind of tetra before. They were just plain silver with a black spot on their caudal peduncle, and no other traces of any pattern or anything. But they were different nonetheless, so I bought them for $1.65 each (who could beat that). The only tetra label on the tank was for Pretty Tetras, but there were none of those in the tank.

I brought them home and emptied them into a container so I could get a better look and snap a few pictures of them. Here are the pictures I took. In the last two photos, it's easy to tell that they had already colored up quite a bit. I began to see a bit of black on their anal fins, and yellow on their adipose fins.









A few minutes after putting them into my tank, they rewarded me for rescuing them by showing their true colors. They were definitely not plain-looking anymore. Their bodies were a pearly silver color with plenty of gold iridescences, and on their tail, they now had a bold design similar to the Mickey Mouse design in a platy, only the "ears" were a very bright white. The design on their tail is clearly visible from across the room.

They are schooling with my Cardinal Tetras for the most part, but they tend to prefer the upper levels of the tank while the Cardinals stay more near the bottom.

Here is a picture of what they look like now:



But I still have no idea what kind of tetra they are. I think they might be the species that Corydoras hastatus is meant to mimic, as their coloration looks very similar. I don't know the scientific name of that species however, if that's what these fish are.

Anybody have any ideas?


[/font][/font][/font][/font][/font]

---

I'm not your neighbor, you Bakersfield trash.

It is, without a doubt, a Hemigrammus sp.. I have recieved shipments of Hemigrammus hyanuary, which look very similar to the fish in question and is what I believe them to be.

EDIT: Hyphessobrycon elachys school with hastatus in the wild, though I fail to see how imitating a two inch long tetra would benefit the corydoras in any way.








Last edited by Cup_of_Lifenoodles at 27-Apr-2005 23:01

This is the only picture of Hemigrammus hyanuary (January Tetra) I could find on Google that resembles my fish, and even it doesn't look like mine very much.



But I agree, it seems to be a Hemigrammus species.

They seem to be pretty feisty, and they are constantly flaring their fins at each other and at the Cardinal tetras. I put some bottom feeder wafers in, and they were easily competing with my two 4" koi (don't ask) for them. And those koi are bruisers.[/font]

---

I'm not your neighbor, you Bakersfield trash.

Hemigrammus hyanuary was my first thought too. Here is a nice picture of one from Israquarium (WARNING: text is in Hebrew, and needs plugins to be displayed even if you can understand Hebrew, which I can't ...). Once these new Tetras colour up, if they resemble this fish, chances are they're hyanuary, which a Google search informs me rejoices in all sorts of interesting common names - January Tetra and Costello Tetra to cite two.

EDIT : Argh, looks like Cory_Addict found the exact same picture!!!!


Last edited by Calilasseia at 27-Apr-2005 22:51

Panda Catfish fan and keeper/breeder since Christmas 2002

I found them! They are Aphyocharax paraguayensis!

Haha... Aphyocharax. That would explain their feisty and outgoing personalities. These tetras have lots of personality.

[/font]

---

I'm not your neighbor, you Bakersfield trash.

Well, I guess I'll have to eat my own words, then.

Hmm...it seems that this species is found alongside corydoras hastatus as well. Why all the mimicry?


Congratulations--they are quite striking.

Last edited by Cup_of_Lifenoodles at 27-Apr-2005 23:06

My only guess is the whole "safety in numbers" thing. Because the two species look alike, they school together to lessen the chance of any individual fish being eaten. But because they are two completely different kinds of fish and fill different niches in their habitat, they don't have to worry about competition with each other. It actually seems like a win/win situation to me...

---

I'm not your neighbor, you Bakersfield trash.

Yes, but isn't three species a bit excessive?

Plus, Corydoras pygmaeus reputedly schools with Hemigrammus levis in the wild. There must be a benefit to all this mimicry somewhere ...

Panda Catfish fan and keeper/breeder since Christmas 2002

So who's mimicking who? I used to think it was the corys that were mimicking the tetras, but now it seems to be the other way around...

---

I'm not your neighbor, you Bakersfield trash.