A very slim needlefish of the surface, half a meter (20 in) long, with a flattened tail stalk carrying a hard keel on each side. Those keels are the identification and the reason for the name: no other needlefish here has them.
A keel does for a fish what it does for a boat - it stabilizes a body that is being driven hard and steers badly. Needlefishes accelerate along the surface in straight lines and leave the water regularly, and the keels keep the tail tracking through it.
The skeleton is green. Needlefishes deposit biliverdin, a bile pigment, in their bones, and a filleted fish is startlingly green inside - harmless, and enough to put off anyone who has not seen it before.
It hunts small fish in the top half meter, where the glare from above hides it from below, and it spawns by attaching eggs to floating weed with fine sticky threads. Like its larger relatives it is a hazard around lights at night, when a startled fish will run in a straight line at the surface without checking what is in the way.
- very slim silver fish at the surface with long thin jaws full of fine teeth
- flattened tail stalk with a distinct keel on each side, unique among local needlefishes
- blue-green back, silver flank, dark line along the side
- length up to 50 cm
Why it's threatened
Threat classification from the IUCN Red List.
