Smallmouth Hardyhead (Atherinosoma microstoma)
San Diego County, California, US
A dense shoal of various hardyheads (Atherinidae)
A dense shoal of hardyheads (Atherinidae)
Image captured while free diving
The Atheriniformes, also known as the silversides, are an order of ray-finned fishes that includes the Old World silversides and several less-familiar families, including the unusual Phallostethidae. They are found worldwide in tropical and temperate marine and freshwater environments.