Atlantic sixgill shark
| Atlantic sixgill shark | |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Division: | Selachii |
| Order: | Hexanchiformes |
| Family: | Hexanchidae |
| Genus: | Hexanchus |
| Species: | H. vitulus
|
| Binomial name | |
| Hexanchus vitulus Springer and Waller, 1969
| |
| Distribution of Hexanchus vitulus (red) and Hexanchus nakamurai (blue) | |
The Atlantic sixgill shark (Hexanchus vitulus) is one of the five extant species of the Hexanchidae family of cow sharks. They are found in the Atlantic Ocean at depths that are greater than 300 meters. Due to their habitat being difficult to access for humans, they are rarely encountered and hard to study. The Atlantic sixgill shark is very similar to other species of cow shark in terms of its morphology and growth rate in deep sea waters. It is believed that this is due to the abiotic and biotic factors in relation to the depths at which they are found. It was first described as its own species in 1969, but was later synonymized with the morphologically similar bigeye sixgill shark (Hexanchus nakamurai). However, a study published in 2018 resurrected the species on the basis of molecular data.