Flat needlefish

Although they have no spines, they do have several soft rays. About 23-26 rays are on the dorsal fin and 24-28 are on the anal fin.^[7] They have 86-93 vertebrae.^[7] Dorsally, flat needlefish are blueish, white ventrally, with dark blotches and 12-14 vertical bars in the middle of their bodies.^[8] Flat needlefish have elongated bodies, with scythe-shaped pectoral and anal fins.^[7] They also have a dark lobe on the posterior part of their dorsal fins.^[7]

The longest recorded flat needlefish measured 140 cm.^[9] Measurements for flat needlefish body length do not include their caudal fins and heads because the fish's long jaws are often broken off.^[7] The largest recorded weight for a flat needlefish was 4.8 kg.^[9]

Flat needlefish are found worldwide in tropical and temperate seas.^[7] In the Eastern Atlantic, they are known from Cape Verde and Dakar to Moçamedes in Angola.^[10] In the western Atlantic, they are known from the Chesapeake Bay south to Brazil.^[11] They are found throughout the Indian Ocean,^[7] and in the western Pacific from the southern islands of Japan to Australia^[12] and Tuvalu.^[13] A few specimens have been collected from Syria to Israel in the Mediterranean Sea,^[14] likely migrants from the Red Sea.

Flat needlefish usually live in neritic ocean waters near islands,^[15] estuaries,^[16] and near coastal rivers,^[17] where they feed on smaller fish^[4] and occasionally gather in large schools.^[5]

Flat needlefish lay eggs, which attach themselves to floating debris by filaments on the surface of each egg.^[18] Only the left gonad in both sexes is developed, and in males, the right gonad is sometimes wholly absent.^[19]