Tetra a tall dorsal fin characterized by a short connection to the fish’s body. Additionally, tetras possess a long anal fin stretching from a position just posterior of the dorsal fin and ending on the ventral caudal peduncle, and a small, fleshy adipose fin located dorsally between the dorsal and caudal fins. This adipose fin represents the fourth unpaired fin on the fish (the four unpaired fins are the caudal fin, dorsal fin, anal fin, and adipose fin), lending to the name tetra, which is Greek for four. While this adipose fin is generally considered the distinguishing feature, some tetras (such
Pomadasys stridens Pomadasys stridens Pomadasys stridens, the striped piggy or lined piggy, is a grunt from the western Indian Ocean, it is one of a group of Indo-Pacific marine species which have colonised the Mediterranean Sea through the Suez Canal from the Red Sea, a process known as Lessepsian migration. "Pomadasys stridens" has a silvery body which is slightly darker dorsally than it is ventrally, it has 3-4 golden-brown stripes along its body, merging towards the caudal peduncle, and a dark blotch on the operculum. It has a relatively large head with a small, slightly oblique mouth and two pores on the