The ampullae of Lorenzini on this chimaera are the two rows of dots on its snout (NOAA)
Ampullae of Lorenzini are a network of electroreceptors, sensory organs that detect electric fields in water, found in chondrichthyes (sharks, rays, and chimaeras). The ampullae are a series of symmetrical pores, concentrated around the snout and nose, connected by gel-filled canals. They can conduct electrical impulses so small, that chondrichthyes are likely to be more sensitive to electric fields than any other group of animals. Because all muscle contractions produce a weak electrical field, these electroreceptors make sharks, rays, and chimaeras highly capable of detecting other organisms, such as prey, nearby in water.
Ampullae of Lorenzini, shown in red, are a electroreceptors that can detect electrical impulses from other organisms in water.