It has a narrow caudal peduncle and a strongly bi-lobed caudal fin, a mouth with an incised upper jaw, and an eye with an adipose eyelid.
The back is blue-green, with silvery sides and belly; the sides feature up to eight black spots of decreasing size, starting from the edge of the operculum and extending approximately halfway down the body. A ventral keel, consisting of a series of small bony shields, extends from the gill region to the insertion of the anal fin. It can reach 30 cm in total length. It forms schools of thousands of individuals that occupy the pelagic portion of larger lakes, advancing to the coastal zones in winter and during the breeding season. It feeds on plankton; however, its diet differs from that of the other two important planktophagous species—whitefish and bleak—with which it coexists. It spawns in June-July, at night, near the shore, when water temperatures are above 15°C. Each female lays several tens of thousands of eggs on gravelly bottoms, in half a meter of water. Shad is the most widely caught fish in Lake Garda (2,000-3,000 quintals annually), along with whitefish. It was released into Lake Caldonazzo, where it has acclimated. Its flesh is good, although it has many fine bones.
Dialect: scarabina (small size); sardena (medium size); agom or agon (large size).
G. TOMASI, 2004 - The Three Hundred Lakes of Trentino. Ed. Artimedia – Temi, Trento, 535 pp.
