Corydoras 'julii"

[Tony C]

I cleared out the "julii" tank at my LFS today and wanted to confirm the ID, are they all trilineatus? A couple have odd patterns to them and I wasn't sure if that was within the normal range of variability for the species or if something else hitched a ride with them.













Thanks!

[Narwhal72]

They are all trilineatus. C. julii has a spotted pattern to the head and these all have a reticulated pattern.

[Tony C]

They are all trilineatus. C. julii has a spotted pattern to the head and these all have a reticulated pattern.

I know none are true julii, just wasn't sure if the last two were trilineatus or "contaminant" species since their patterns are so different from the rest.

[Narwhal72]

There is a lot of variation in trilineatus so the differences in pattern could be chalked up as just individual variation.

Without collection data it really would be impossible to tell.

Keep in mind that most of the "julii" cats sold in lfs are farm raised florida fish and not wild caught.

Andy

[Karsten S.]

Hi,

C. julii has a spotted pattern to the head and these all have a reticulated pattern.

although frequently copied/repeated this is not quite true.
There are C. julii with reticulated pattern as well as C. trilineatus with spotted pattern; both is unusual but does exist.
The pattern is not a safe criterion for distinction of these species.
Especially C. trilineatus is very variable with respect to pattern.

I would also favour C. trilineatus but without origin it is difficult to be absolutely sure.
Only the specimen in the second last picture looks a bit weird.

Is the pectoral fin spine really kind of orange ?
This could be a hybrid of C. trilineatus und C. sterbai. This has even been reported among WC C. trilineatus.

Cheers,
Karsten

[rmc]

Interesting note on the possible hybrid Karsten! The eyes and body shape look rather "sterbai" too!

I believe I have the C.julii with a bit more reticulation than the spotted C. julii. From near Belem in Brazil - wild caught. It is no where near this reticulated! It's just kind of irregular spots (they're not round). Unless you are talking about a different location of C. julii. The best picture I have that shows this is one I took of a sick fish trying to get a close up of the disease. It didn't help that one, but you get the idea about the spots. I attached the picture to this post

[Tony C]

I would also favour C. trilineatus but without origin it is difficult to be absolutely sure.
Only the specimen in the second last picture looks a bit weird.

I'm assuming they are farmed fish, my LFS doesn't usually deal in wild caught corys.

Is the pectoral fin spine really kind of orange ?
This could be a hybrid of C. trilineatus und C. sterbai. This has even been reported among WC C. trilineatus.

Cheers,
Karsten

The one you pointed out as weird does have an orange tint to the spines, not as orange as a sterbai but it's definitely there. The others are iridescent, any orange on them in the pics is just from lighting. The hybrid idea does seem plausible with its coloring and odd pattern.