Atlantic thread herring

Opisthonema oglinum

Family Clupeidae - herring

Distinguishing
Characteristics
Body moderately elongate, compressed; color green-blue above, sides and belly silvery, sometimes with dark horizontal lines on upper body; faint spot behind opercle; last ray of dorsal fin elongate; dorsal and caudal fins with dusky tips; typical herring mouth (short, deep lower jaw hidden by wide rounded upper jaw); belly with serrated keel; no frontal notch in upper jaw; no enlarged scales on back in front of dorsal fin; shoulder under opercle with 2 small lobes.
Similar Species
Atlantic thread herring, gizzard shad and threadfin shad are the only herrings (off Texas) where the last dorsal ray is elongated and filamentous; Atlantic threadfin herring has a terminal mouth (subterminal in gizzard shad), no frontal notch on upper jaw as in gizzard shad, also has 2 lobes on shoulder under opercle (none in gizzard and threadfin shad); scaled sardines also have 2 lobes on shoulder but does not have a long filamentous last dorsal ray.
Habitat
Gulf
Maximum Size
38 cm (15 in), common to 20 cm (8 in)
Fin Element Counts
D. 17-21; A. 21-25 (explain)
Other Common Names
Previous Scientific Names
Comments
State size/bag limits