And to OP, i think the store was just too lazy to update the tag on the tank.
After all even a 2 year old can tell the difference between a gar and a bichir
One way to tell the difference between a channa and a polypterus is by looking at their dorsal fin.
As you can see, a bichir's dorsal fins are sort of spiky while a snakehead's fin is more uniform, like the sails on a spinosaurus
And also snakeheads have fins on the bellies too and the tail fins and dorsal fins are seperated. While poly fins are just all the way from the back to the tail.
My bichir that look exactly like the one in this post was labeled "Polypterus senegalus" but clearly is not. I though it was a a Palmas basedon a website identification chart with pics but aparently its a LAP. Good to know. Havent really noticed the whole upper jaw lower jaw thing... I have a endli (also in pic below) and i cant really tell the diff in jaws... maybe im slow or maybe its noticeable when mouth is open.
Looked closely at some pics (and even atmy own posted above) and NOWWWw i see what the upper lower jaw deal it. Lower jaw seems to be angles downwards towards the back and is much deeper than upper jaw like my albino, delhzi, ornate etc etc. GOTCHA, yes its a Lap. lol
^ Yup. Some ignorant LFS sell them as senegals. And thats a good deal!
If you look from sideways, lower jaw species like lap and endli looks as if they are smiling all the time.