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Hi All,
I was at my LFS tonight and I saw these Corys. They were labeled "Blotchy Corys" and they were priced at either $4 USD or $6 USD (I can't remember which).

I suspect they are identifying the cats as . But these fish did not look much like the photos of adult C. blochi (unless their coloration is very immature (see my comment below)).

Here's how I describe these fish:

1. They have a rather long snout.
2. They have one prominent broken stripe down the midlateral side.
3. There are two very weak broken lines above and below the midlateral stripe.
4. Most of the body is covered with small spots.
5. The head is covered with a reticulated pattern above the eyes, and small spots anterior to the eyes and onto the snout.
6. The tail has about 6-7 vertical stripes.
7. The dorsal fin looks like it should have a large black spot on the tip of the fin (unfortunately, all of the fish had severely torn dorsal fins, so all you can see is a tiny area of black just along the torn margins, so I'm inferring that the rest of the missing dorsal fin would also have been black).
8. Finally, at least two fish had a slightly darkened dorsal spine (which seemed to be the anterior edge of the speculated large dorsal fin spot), but others fish in this group did not.

There are some common Cory color patterns that are missing too. These fish DO NOT have

1. a black hood over the head,
2. a vertical black stripe through the eyes,
3. a yellow-tan area behind the head, or
4. a large black spot spreading from the upper anterior body onto the dorsal fin.

These fish were all about are about 2-3 cm SL. Since the fish aren't very big yet, I'm inclined to think that their color patterns may not be fully developed, and I wouldn't be surprised if their body spots, the lateral stripes, the head reticulation, or the dorsal fin change color patterns as they age.

If they are immature, then maybe they could be C. blochi; but shouldn't we expect to see at least some evidence of the black stripes through the eye and from the dorsum up onto the dorsal fin by this size? So I don't think they are C. blochi.

If not C. blochi, then what are they? As I try to figure this out, I'm looking at the following possible spp.:
(my personal guess, at this time)
(but I think the snout is too long to be C. gomezi)
(my lease likely guess, because C. acutus appears to have more tail stripes than I saw on these unknowns.

Thanks for the help. Cheers, Eric

Here's one more photo.

I would say Corydoras leopardus. There is a lot of variability in pattern with this species and they are fairly common in the trade.

I have a group of them and they appear very similar to yours.

Andy

From my understanding is the fish most often imported and frequently offered as

Even with the damaged dorsal fins, these Corys are definitely interesting to me, and I don't have any "long nose" Corys of my own. But I didn't buy them for two reasons: 1) At the time, I didn't know what they are, 2) I still don't have extra tank capacity for new fish (making matters worse, I just got a bunch of Cory eggs at home, and soon I'll need to make room for the fry).

If these had turned out to be a rare Cory, or at least a very underpriced species, I would probably go back and get them. The LFS had at least 4 of them and I would get them all. But if they are leopardus, and if leopardus are "fairly common" in the marketplace (although in truth I've never seen them in my area before, or in any LFS in San Francisco or Sacramento when I've taken shopping trips to those towns in the past), then for me to buy a "fairly common" fish when I don't have extra space is not a smart decision.

Just to confirm that these are not immature blochi, does anybody have personal experience with blochi? Can you tell me if young blochi would or would not look like this also?

Thanks again, and have a nice day! Eric

Nabobmob1 wrote:From my understanding

C102

is the fish most often imported and frequently offered as

Corydoras leopardus

Sorry I missed your post - I was typing my other response while you posted this, so I didn't see your comment about C102 until later.

From the C102 photos on the CLOG, the Corys at my LFS do resemble C102 as much as they look like C. leopardus. I see that the CLOGs for both C102 and C. leopardus list Peru as a locality. Since the C numbered fish aren't yet identified to a species, isn't it possible that C102 is C. leopardus?

Thanks, Eric

Hi Eric,

you are right, this is the idea of C(W) numbers, we don't know yet as the scientists have not yet analysed this form explicitly.

C. leopardus and C 102 are very close and it is possible that they will prove to be the same species.
In this special case we even have DNA sequencing of both which supports this.
But, as for the number C 102 there is no exact origin given (only Peru) and it is rather probable that the used material of C. leopardus also did not come from the type locality this information is rather weak. The origin of the both specimen used for the sequencing is given as "Amazon"...

With all uncertainties described above I would also tentatively call them C 102.
They correspond to the form that we get from Peru under the name C. leopardus.

Cheers,

Okay, thanks Karsten.

Kamas88 wrote:But, as for the number C 102 there is no exact origin given (only Peru) and it is rather probably that the used material of C. leopardus did not come from the type locality this information is rather weak. The origin of the both specimen used for the sequencing is given as "Amazon"...

If I understand you correctly, it sounds like the locality data is ambiguous for both the C102 and the C. leopardus used for DNA analysis. I just looked up the original formal description of C. leopardus by Myers (Four new fresh-water fishes from Brazil, Venezuela and Paraguay. Proc. Biol. Soc. Wash., vol. 48, pp. 7-13. February 6, 1935.) and this is what he wrote: (color emphasis added by me)

George Myers wrote:Two Cyprinodonts, a Callichthyid catfish and a genus of Cichlids are herewith described as new from the collections of the United States National Museum. It will be noted that two of the new forms are based on aquarium specimens without accurate locality. ... The present two species, however, seem to be so well-marked ... that there can be no great objection to naming them from the material at hand, especially since we can be fairly certain of the general area from which they came. ...

Corydoras leopardus, new species.
Holotype. — U. S. N. M. 93305, 41 mm. standard length; Brazil (probably the Amazon or one of the coastal streams immediately to the south); collected in 1933 by Karl Griem; received from Mr. Richard Büttner of New York. Paratype. — U. S. N. M. 93306, 23 mm. standard length; same data.

... My two specimens were recently imported individuals collected by Mr. Griem and shipped to me alive by Mr. Richard Büttner of the Empire Tropical Fish Import Company of New York.

Indeed, even the original holotype and paratype of C. leopardus were aquarium fish from New York. What do we do with that?!?

Those tetras may well be the cause of the damage to the dorsal fins.

mummymonkey wrote:Those tetras may well be the cause of the damage to the dorsal fins.

Yeah, I wondered about that, too. Good possibility.

I don't know if the Corys arrived at the LFS looking like this, or if the damage happened at the LFS; I'm inclined to suspect that it happened at the LFS in the tank you see in the photos. And yet, for as long as I observed the fish yesterday (about 20 minutes), the tetras left the Corys alone. So I wondered if the Corys' intact dorsal fins, with their big black dots, might have resembled "targets" waiting to be attacked by other fish. Now that the black spots are chewed off, the Corys seem to be left in peace by the other fish.

Hi,

bekateen wrote:...Indeed, even the original holotype and paratype of C. leopardus were aquarium fish from New York. What do we do with that?!?

there are even worse cases. At least there is still a holotype/lectotype which can be analysed.
By the way, the type locality has been restricted (by Nijssen & Isbrücker, 1980) to Brazil, Parà, Maracana.
This might be a bit too far from Peru...

Some decades ago the scientists greatly underestimated the diversity of the genus and lumped many species together (sometimes short snouted ones with long snouted ones, sometimes similar corys from location that are very far apart,...).
In some cases this has been corrected (leading to new scientic names) but I'm rather sure that in many cases this has not been done for many different reasons.
This material with a wrong scientific name on the label is sometimes also used as a reference for genetics (I'm pretty sure in some cases) or other phylogenetic analysis. These paper are later on again reused in further studies...
But I don't see any realistic solution for this problem, there are just too many (species) of these cute little fish.
It's a nightmare or a dream (depends from the perspective)...

Cheers,

THIS is why I didn't specialize in systematics during my education. Just give me the good old days where we would throw two similar looking organisms together to see what happened - if they spawned successfully, and if their offspring were fertile, then we'd call them the same species. LOL (in truth, it hasn't been that simple since before I started my career, if you take into account the complications caused by natural interspecific hybrid zones, etc.).

I suppose I've always been a lumper, not a splitter; in particular, splitting populations of similar organisms based on distance between the populations has never been a very high priority to me, given that many species on Earth have wide ranges. If I was a professional taxonomist, I would probably be inclined to assign separated populations to one species as long as some gene flow could be demonstrated between the populations; or at most I might call them subspecies. But again, naming species is not my job, nor even my formal training.

Now that I think about this, I realize that I probably just annoyed a bunch of people who do that work for a living - Sorry about that; no harm intended.

Cheers, Eric

My sincere apologies for digging up an old topic, but I purchased 4 Corydoras trilineatus yesterday of which one was off.
I believe it's either leopardus or C102.
Is someone able to shine a light on this?

Tanganyikafreak wrote: ↑11 Dec 2020, 16:08My sincere apologies for digging up an old topic, but I purchased 4 Corydoras trilineatus yesterday of which one was off.
I believe it's either leopardus or C102.
Is someone able to shine a light on this?

Hi Tanganyikafreak,

Yes - One of my favorite corys! Lucky for you to find it.

Cheers,
Eric

Much appreciated.
I actually went for as much trilineatus as possible, but they only had 4 of which 1 odd looking one.
I can't put my finger on what it is, but I completely fell for that 1 little oddball.
The pattern, its shape, the slightly elongated nose. For me it's a winner.
Now on a mission to find as much specimens as possible!

Tanganyikafreak wrote: ↑11 Dec 2020, 17:13I can't put my finger on what it is, but I completely fell for that 1 little oddball.
The pattern, its shape, the slightly elongated nose. For me it's a winner.

I agree. For me, it's a combination of the elongated nose (which in big adults gets a little bit of a concave curvature, almost like a lineage 1 cory), the wider separation between the black markings, (i.e., more white / silver showing through), and the thicker, bolder black lines that make the fish look so nice. Also, I think the fact that these lineage 8 subgroup 4 fish get larger than the lineage 9 trilineatus makes them look neat in my judgement.

Good luck on the hunt,
Eric

Thanks

These are lovely fish, I've always liked the cryptic squiggles of trilineatus and these have a similarly pleasing pattern but with a different form. The larger size, longer snout and white fringing around the dorsal spot really set them apart. I got three of them about a month ago from a good shop, then another two on a subsequent visit, and last week I picked up the remaining three, making a nice school of eight

That is just great
I hope I'll have the same luck as you

Finally, today I received 8 additional specimens to go with my lonely specimen

Beautiful!

Here are some photos

You have one C. trilineatus in the group, your last photo.

Cheers, Eric

I knew someone would jump on that
There's 4 trilineatus next to my 8 C102 (and 14 aeneus for that matter)