This is going to be about the differance between what is a real gar, and what is either usually a pike characin or needlefish misidentified as a gar. The first thing you'll want to look at is the caudel fin, or tail fin. Is it forked or rounded? If the tail is round it is most likely a gar, if not. it is a pike characin or needlefish. Another thing you can look at is the number of fins on the dorsal or top side of the fish, If there is one fine near the caudel fin or tail of the fish, then it is probably a gar, if there is one fin and then a smaller fin before the tail, it is a pike characin. The last way to tell would be looking at the scales. Gars have ganoid scales which are very hard and diamond shaped. They are easily seen, compared to the needlefishes scaleless/tiny scaled skin. If the fish's scales are easily seen, it has only one fin on its dorsal side, and a round tail. It is a true gar. If it has two fins on the dorsal side, or it has a forked tail, or its scales are almost invisible, it is either a pike characin or needlefish.