Actually I experienced the mislabeling from one of the most well known fish exporters in U.S., I ordered Zonatus and received either Guttulatus or Hartwegi (not clear yet but one thing for sure is that they are not Zonatus).
Then he informed me that this was not among the fish he breeded but he bought them from one of the local breeders as Zonatus.
Psylant,
Currently, I cannot add pictures but work on below link and you will see that one of Mo's breeding pair has no red on the head whereas the other pair has red heads.
The fish looks very much like the Coatzacoalcos. And Cenk brings up a very good point. ID'ing these fish at a small size can be a real guessing game at times. And I DON'T buy into the "It's a hybrid" guessing game that goes on when there's an unknown fish. I know they're out there, but if you read back on a lot of these threads, there would be an onslaught of hybrids of all flavors in tanks.
Here's some photos ofsome of the fish mentioned for comparison. First is Synspilus @ 3-4". You said yours has a red head. This red? Note the absence of that complete horizontal line.
Zonatum at the same size. Note the complete horizontal line:
Coatzacoalcos can look dramatically different even among siblings...and change as they grow. Here's the fish at three inches:
Four inches
Same size...different fish in the group
One thing that remains consistent with ID'ing coatzacoalcos is that they will have a red band of dots across the snout. You can see it in this photo:
I don't think your fish is synspilus. THe red in the head is more spangled and not a complete red like above. It could be a coatzacoalcos...but the overall shape of the head is different. If pressed I would say it's either fenestratus or hartwegi.
Wow. Thanks for the in depth analysis, Mo. I'll keep waiting to see what this develops into and post more pictures in another month or so. I'm not sure I've ever seen a fish on this site be so unidentifiable hahaha.