Inland Silverside Identification Guide

Key identification features

• Small, slender, laterally compressed body, usually 2-4 inches (5-10 cm)
• Translucent greenish-tan back with a bright silvery stripe along the midline
• Two separated dorsal fins, the first small with a few thin spines
• Large eyes relative to head size and a small terminal mouth
• Forked tail and a generally delicate, streamlined build
• Body often shows a faint yellowish or greenish cast when viewed from above in shallow water

Common look-alikes

• Atlantic Silverside: very similar in appearance but larger and restricted to fully marine coastal waters
• California Grunion: notably larger with a stouter body and a Pacific coastal range
• Mosquitofish: lacks the silvery lateral stripe and has a rounder, less streamlined body

Where you'll see one

Widespread in brackish estuaries and freshwater rivers, reservoirs, and coastal plains across the southeastern and Gulf Coast United States, often schooling near the surface. It also tolerates fully fresh inland waters far from any coastline and has been introduced to many reservoirs outside its native range.