Telling apart Synodontis eupterus and nigriventris

[Quokka]

Hello everyone,

Over here in South Korea, the most common Synodontis is eupterus. Heck, if it is just named "Synodontis", chances are it is 99% just eupterus!

The only other relatively well known species are lucipinnis (as petricola) and mulpitunctatus(The beautiful cuckoo catfish).
Some places sell hybrid synos too...and every now and then I see a chance angelicus. But never the original upside down catfish, nigriventris! Nuts huh? Evem though they are smaller and more peaceful! Maybe eupterus are better bred in huge numbers?

I have seen my fair share of eupterus, but last week I stumbled across what I am fairly sure are nigriventris. The little cats were with a few ture baby eupterus, but somehow they seemed different....But since I have never seen a live nigriventris before I cannot really tell.

Can anybody give me a surefire way to identify between the two? As I said in Korea Synodontis are not popular so I have nobody to ask here ...maybe there are subtle or definite differences in coloring, spots, head shape, fin shape? They were way darker than usual eupterus juveniles, but based on my experience young eupterus do not have a big difference in the dorsal fin(which will grow to be big and beautiful) I got confused.

Can someone please help separate the two? I am kicking myself since I did not take pictures at that time After seeing way too many baby eupterus I think I have gone paranoid!

[Bas Pels]

Whilr your main thinkg is to separate auteris from nigriventris, you basically want to be certain they are nigriventris. And not nigrans, for instance.

Eupterus is the only syno with the featherlike dorsal. S nigriventris have black bellies, the very name nigriventris means with with black ventral (ventral is belly, and the rest)

But I can´t say whether all Synos with bleck bellys are nigriventris. S nigrans are for instance quite often offered here as nigriventris, these are blak all around. So also quite easy to separate.

Perhaps you are ab le to get a photo of them?

[bekateen]

I agree with Bas Pels. Once you know what to look for, the species (eupterus and nigriventris) look very different. Nigriventris tend to have spots like leopards - broken circles with off colored centers (https://www.planetcatfish.com/common/im ... e_id=13112). Eupterus tends to have solid black spots (https://www.planetcatfish.com/common/im ... ge_id=1583). However very small eupterus have a totally different pattern (https://www.planetcatfish.com/common/im ... ge_id=4193).

Cheers, Eric

[Quokka]

Whilr your main thinkg is to separate auteris from nigriventris, you basically want to be certain they are nigriventris. And not nigrans, for instance.

Eupterus is the only syno with the featherlike dorsal. S nigriventris have black bellies, the very name nigriventris means with with black ventral (ventral is belly, and the rest)

But I can´t say whether all Synos with bleck bellys are nigriventris. S nigrans are for instance quite often offered here as nigriventris, these are blak all around. So also quite easy to separate.

Perhaps you are ab le to get a photo of them?

Thanks Bas!
By nigrans you mean nigrita? Also forgot the black belly part! It IS really black! Haha my bad!

I agree with Bas Pels. Once you know what to look for, the species (eupterus and nigriventris) look very different. Nigriventris tend to have spots like leopards - broken circles with off colored centers (https://www.planetcatfish.com/common/im ... e_id=13112). Eupterus tends to have solid black spots (https://www.planetcatfish.com/common/im ... ge_id=1583). However very small eupterus have a totally different pattern (https://www.planetcatfish.com/common/im ... ge_id=4193).

Cheers, Eric

Thanks for the links Eric! Now I can see the differences a lot more clearly! Besides the colors the shape of the head seems different too! And side by side the colors and pattern are definitely recognizable!

Maybe I can finally keep the true USD catfish! Next time I will bring a photo for reference just in case!

[racoll]

Swimming in mid-water upside down is also a clue to look out for.

[Quokka]

Swimming in mid-water upside down is also a clue to look out for.

Thanks!
I saw baby eupterus do that quite often too....but come to think of it, as not as much as the origical USDC nigriventris would I guess! Upside down midwater....now I feel I have all the weapons necessary to tell the difference! Haha

[bekateen]

Yes, baby eupterus will also swim upside down sometimes.

[Bas Pels]

@ By nigrans you mean nigrita?

Yes, sorry for not verifying the spelling

[Quokka]

@ By nigrans you mean nigrita?

Yes, sorry for not verifying the spelling

Naaaah I am extremely thankful for your input!
Honestly both nigrita and nigriventris have their own charms! I would be happy to have either!

[Birger]

you dont really want nigrita...they are big bullies and greedy feeders.
the picture you have above for nigriventris is the zebra kutu variant.
The regular nigriventris have a variety of colors and patterns.

Birger