Clupeiformes is the order of ray-finned fish that includes the herring family, Clupeidae, and the anchovy family, Engraulidae. The group includes many of the most important forage and food fish.

Clupeiformes are physostomes, which means that their gas bladder has a pneumatic duct connecting it to the gut. They typically lack a lateral line, but still have the eyes, fins and scales that are common to most fish, though not all fish have these attributes. They are generally silvery fish with streamlined, spindle-shaped, bodies, and they often school. Most species eat plankton which they filter from the water with their gill rakers.

Clupeiformes. Retrieved January, 01 2022, from en.wikipedia.org/wiki/Clupeiformes.

Clupeidae is a family of ray-finned fishes, comprising, for instance, the herrings, shads, sardines, hilsa, and menhadens. The clupeoids include many of the most important food fishes in the world, and are also commonly caught for production of fish oil and fish meal. Many members of the family have a body protected with shiny cycloid (very smooth and uniform) scales, a single dorsal fin, and a fusiform body for quick, evasive swimming and pursuit of prey composed of small planktonic animals. Due to their small size and position in the lower trophic level of many marine food webs, the levels of methylmercury they bioaccumulate are very low, reducing the risk of mercury poisoning when consumed.

Clupeidae. Retrieved January, 01 2022, from en.wikipedia.org/wiki/Clupeidae.