The Deep Sea Hatchetfish is a collective term for a group of approximately 45 deep-dwelling ocean species.
The common name for the group understandably comes from their relatively hatchet-shaped body structure. However, they obviously appear quite different from the numerous freshwater hatchet fish popular in home aquariums.
Scientists know little about the lifecycle of the various types of Deep Sea Hatchetfish. Nature, it seems, still likes to maintain her mysteries. Some experts believe they possess a short lifespan of less than one year, yet not all ichthyologists agree.
Deep Sea Hatchetfish Physical Description
The numerous varieties of Deep Sea Hatchetfish range in length from 1-6 in (2.5-15 cm). Most of these have a covering of delicate scales, the colors of which vary by species, but include silver, brown, or dark green.
Perhaps their most distinctive feature remains their large, tubular eyes, which typically, though oddly, point upwards in their heads. They are also extremely sensitive to changes in light patterns.
The creatures also possess many photophores which generally sit along the body length. These they use to attract their prey in the dark ocean depths. Many types of Deep Sea Hatchetfish are also covered in large spines.
Deep Sea Hatchetfish Distribution and Ecology
The Deep Sea Hatchetfish lives in the Atlantic, Indian, and Pacific Oceans, where they inhabit waters ranging from tropical to temperate. They may occasionally reach depths of as little as 164 ft (50 m) but they most typically prefer the 656-4,920 ft (200-1,500 m) range.
Most likely they prey on plankton and a variety of small species. Perhaps they migrate to shallow water at night to feed. Nothing is known about their own predators, but their photophores may help to hide them.
Their mating habits are also a mystery. Yet, and most interestingly, scientists know that the young bear little resemblance to the adults.