- Color of body dark blue shading to silvery, white underneath
- Dorsal fin bluish, others brown-black
- Two dorsal fins, the first lengthy, its front forming a peak
- Two anal fins, the anus well in front of the first
- Upper jaw is prolonged into spear
- Its cross section is round
Longbill spearfish are found offshore in deep water.
These fish are uncommon. Available data indicate that spearfish matures at 2 years of age and rarely lives past 4 to 5 years. They are pelagic and feed at or near the surface, mainly on fishes and squid.