Thanks for this info!
I bought 5 SAEs at LFS and didn't pay attention, they were all in the same tank (labaled as Crossocheilus siamensis). When I released them in the aquarium at home, I noticed that they were not all the same. 2 out of 5 have a thicker side stripe. Now I looked at them from below and the ones with the thicker stripe have that black line on their belly, the others don't.
Here is a photo from the side - far right and bottom middle has black belly line. Do I have a real ones?
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