| Ninja lanternshark | |
|---|---|
 | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Chondrichthyes |
| Subclass: | Elasmobranchii |
| Division: | Selachii |
| Order: | Squaliformes |
| Family: | Etmopteridae |
| Genus: | Etmopterus |
| Species: | E. benchleyi |
| Binomial name | |
| Etmopterus benchleyi | |
Theninjalanternshark (Etmopterus benchleyi) is of the familyEtmopteridae, found in theeastern Pacific Ocean fromNicaragua, south toPanama andCosta Rica. The depthrange of collections is from 836 to 1443 meters along thecontinental slope.E. benchleyi is the onlyEtmopterus species presently known from thePacific Coast ofCentral America.[1]
Thespecies was described from eight specimens collected off the Pacific Coast ofCentral America during an expedition of the Spanish research shipMiguel Oliver byD. Ross Robertson, a researcher at theSmithsonian Tropical Research Institute. Oneholotype and fourparatypes were described and deposited with theUnited States National Museum of Natural History,Smithsonian Institution, Washington D.C.[1]
The ninja lanternshark is coloured black, with the mouth and eyes having white markings around them.[2] The maximum length of male specimens collected during theMiguel Oliver voyages is 325 millimetres (12.8 in), while that of the femalespecimens is 515 millimetres (20.3 in).[1] This species is distinct from other members of theE. spinax clade in having dense concentrations ofdermal denticles closely surrounding the eyes and gill openings.[1]
This ninja lanternshark has a relatively short and conically shaped snout. The teeth in the upper jaw are small, straight and pointed, while the teeth in the lower jaw are larger. The first row of the upper jaw contains about 26-30 teeth, and the first row of the lower jaw contains about 30-36 teeth.[1]
Its fins are small and rounded; the first and seconddorsal fins are either of equal size or the first fin is slightly smaller than the second.[1] A unique characteristic of this species is that it has dense concentrations ofdermal denticles surrounding its eyes and gill slits.
Because the ninja lanternshark is known to live at deep sea depths, it has a very dark coloration to blend in with the lack of light. Although the dark pigment can act ascamouflage that helps hide from predators, it can also be useful when sneaking up on prey.[3] This is because when ninja lanternsharks are feeding in shallower waters, theirluminescent underside has the same appearance as the sunlight filtering down from above and camouflages them from potential predators below. However, when they are in the deep sea, their luminous appearance attracts smaller prey to them which consist of shrimp and other small fish and crustaceans.
The shark was identified by shark researcherVictoria Vásquez. When asking for advice on naming the shark at a family gathering, it was actually her younger cousin who named the shark, pointing out that “ninjas are awesome.”[4] The specific namebenchleyi derives fromPeter Benchley, author of the 1974 novelJaws that was used as a basis forSteven Spielberg's filmof the same name.[1]
