The chimera of the depths (or simply “chimera”) is different from other fish in many ways. This curious animal is scattered throughout the world, between 100 and 1700 meters deep. In summer, sometimes, it rises to the surface, but in winter it looks for the depths, where the temperature variations are smaller.
Its appearance is quite striking, since it has large eyes, a head more prominent than the rest of the body and a rather long caudal fin. And since they can reach between one and two meters, the term “underwater monster” has been attributed to it.
These strange animals are part of the group of chimeriforms, an order of cartilaginous fish. Their skull differentiates them from the rest of abyssal fish, because of which they have constituted a subclass of their own: that of the holocéfalos. In this subclass they are accompanied by other fish known as “ghost sharks.”
Currently, only 47 species of chimeriforms survive.
Characteristics of the chimera of the depths
As we mentioned earlier, its appearance is extremely strange:
- First, they have a large protruding head. It shows a grotesque face due to the appearance of the two mucous channels. His upper jaw is fused with the rest of the skull.
- Second, they have a long, fusiform tail, characteristic of many deep-sea fish.
- Third, their eyes are phosphorescent green, full of photoreceptors to optimize their vision at depth.
These characteristics are what have given the name “chimera”, remembering the monsters of Greek mythology constituted by parts of various animals.
They reach sizes of up to two meters, most of which correspond to its excessive tail. And the females are the biggest. They have the bare body of scales, compressed laterally, developed in length and strongly thinned towards the tail
Its skeleton is cartilaginous, like the elasmobranchs – sharks and rays –. But it only has two gill openings, which brings them closer to bony fish.
Adults lack a spiracle, but this is present during embryonic development.
Another of its most striking features is the spike they have in the front of the spine. With it they can cause deep wounds and even inoculate poison to predators.
Its sting is very painful but it is not fatal for man unless he is allergic.
They feed on mollusks and other small seabed animals, such as crabs, crabs or starfish. It has teeth that are real crushers.
Reproduction of the chimera of the depths
They have pterygopodia that act as male external sexual organs. And, sometimes, a small “pseudoterigopodium” on the head, similar to some prehistoric sharks.
Males take advantage of this fleshy bump between their eyes to hold females during intercourse.
The female deposits the laying and buries it in the sand. Each egg is enclosed in a cornea capsule and covered with hair.
Monstrosa Chimaera: the chimera of the depths of our seas
It is a kind of chimera typical of the northeast Atlantic Ocean and the Mediterranean SeaIt seems to prefer the upper continental shelf between 300 and 500 meters deep.
In the Mediterranean this species is found in depths from 100 meters, but it is more abundant between 500 and 800 meters. There are references of specimens 650 meters deep in the Balearic Sea. And 800 meters deep in the Ionian Sea.