Chimaeras are most closely related to sharks, although their evolutionary lineage branched off from sharks nearly 400 million years ago, and they have remained an isolated group ever since. Like sharks, chimaeras are cartilaginous and have no real bones. The lateral lines running across this chimaera are mechano-receptors that detect pressure waves (just like ears). The dotted-looking lines on the frontal portion of the face (near the mouth) are ampullae de lorenzini and they detect perturbations in electrical fields generated by living organisms.
This image was captured at the ‘Zona Senja’ site near Sulawesi, Indonesia, on August 2, 2010.
Image courtesy of NOAA Okeanos Explorer Program, INDEX-SATAL 2010.
Eerie critters from the deep sea: Predators and Scavengers
For Halloween 2012, deep-sea animals eating or scavenging for food. In order of appearance: Black ghost shark eating a dead fish, galaxy siphonophore digesting a live fish, crab scavenging a whale bone, comb jelly eating another comb jelly (footage courtesy of NHK), small octopus hunting, black-eye squid feeding on a juvenile, Humboldt squid eating squid hatchlings.
This crazy looking fish is called a deep-water chimaera, but it’s not a mythical beast: it’s also called a small-eyed rabbitfish and is related to sharks. It can be found at depths of up to 3000 meters (9800 feet) on the mid-Atlantic ridge.
This one was found there on a trip with the Census of Marine Life. Read more about the Census here - ocean census
Not to be confused with the Rabbitfish, a group of brightly-colored reef-dwellers.
The rat fish is one of the few fish of the order Chimaeriformes that you can see in person. Though a member of an order that dwells up to 2600 meters (8500 feet) below the surface of the ocean, they are capable of living at surface-level relatively easily, and as such are one of the only Chimaeridae (also known as ghost sharks or ghost fish) that are kept in public aquariums.
Chimaera are the closest living relatives to sharks, though they diverged over 400 million years ago. We have abundant fossil evidence of their evolution to their current forms, and they’re one of the most-studied orders of cartilaginous fish. These fish are the only vertebrates to retain vestigial evidence of a third set of limbs.
Illustrations de Ichtyologie ou histoire naturelle générale et particulière des Poissons. Marcus Elieser Bloch et al., 1795.
The narrownose chimaera, Harriotta raleighana, is a longnose chimaera of the family Rhinochimaeridae, found in temperate seas worldwide, at depths of between 200 and 2,600 m. Its length is between 1 and 1.5 m, including a long tapering snout and a long filamentous tail.
Rescue workers on Japan’s North Pacific coast are finding deepsea creatures tossed up from thousands of feet below the ocean’s surface by the tsunami and washed up onto the shore. They’re a fascinating sight, and my thanks to EB contributor Paul Darlaston for providing them. (via: The Star)
*this is an older picture not actually from the tsunami, but from here:
Ghostsharks (aka Chimeras) branched off from their closest relatives, sharks, about 400 million years ago, according to NOAA. To detect prey in the dark depths, chimaeras have sensitive electrical receptors on their heads that can pick up changes in other animals’ electrical fields.
“The Spotted Ratfish (Hydrolagus colliei) is a chimaera found in the north-eastern Pacific Ocean. Often seen by divers at night in the Pacific Northwest, this harmless shark relative gets its characteristic name from a pointed rat-like tail. The ratfish lays leathery egg cases on the bottom of sandy/mud areas which are often mistaken by divers as something inanimate. While mainly a deep-water species, it occurs at shallower depths in the northern part of its range…” (read more)