The Chilean devil ray (''Mobula tarapacana''), also known as the box ray, greater Guinean mobula, sicklefin devil ray or the spiny mobula, is a species of ray in the family

Mobulidae The Mobulidae (manta rays and devilfishes) are a family of rays consisting mostly of large species living in the open ocean rather than on the sea bottom. Taxonomy The Mobulidae have been variously considered a subfamily of the Myliobatidae by ...

. It is often observed worldwide, basking just below the surface in tropical, subtropical and warm temperate oceans, mainly offshore, and occasionally appearing near the coast. It can reach a disc width of up to . Originally believed to be surface dwellers, ''Mobula tarapacana'' have been discovered to feed at depths of up to during deep dives; they are among the deepest-diving ocean animals. Their dives often follow a stepwise pattern, in which the ray dives deeply, then works its way back up by repeatedly "levelling up" for a bit and then moving higher. Sonar observations suggest that rays level up where there are denser layers of prey, suggesting that this is a foraging behavior. Rays display two distinct deep-dive patterns. The stepwise dive pattern, which is usually only performed once every 24 hours, involves diving to the maximum depth and resurfacing after 60 to 90 minutes; a second pattern, which is less frequent, involves diving up to 1,000 meters for a maximum of 11 hours. The latter pattern may be associated with traveling rather than feeding. The ray's behavior may be linked to an organ called the ''

retia mirabilia A rete mirabile (Latin for "wonderful net"; plural retia mirabilia) is a complex of arteries and veins lying very close to each other, found in some vertebrates, mainly warm-blooded ones. The rete mirabile utilizes countercurrent blood flow within ...

'', which is found in rays and in deep-diving

great white sharks The great white shark (''Carcharodon carcharias''), also known as the white shark, white pointer, or simply great white, is a species of large Lamniformes, mackerel shark which can be found in the coastal surface waters of all the major ocean ...

. A veined structure of blood vessels warms the ray's brain at colder depths. Rays stay near warmer surface water for at least an hour both before and after deep diving, suggesting that they are soaking up heat to prepare for and recover from their descent into colder water.

References

Mobula Fish of Chile Pantropical fish Fish described in 1892 Taxonomy articles created by Polbot {{Chondrichthyes-stub