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New Zealand lanternshark
The New Zealand lanternshark (Etmopterus baxteri) is a shark of the family Etmopteridae mainly found off the coast of New Zealand.[1] It can also be found in the Southern areas of Australia and Africa, inhabiting water depths between 500-1500m.[2] These sharks can be commonly known as Baxter's dogfish and giant lantern shark.[2] According to the New Zealand Threat Classification System (NZTCS), this species conservation status is considered non-threatened.[3] DietThese sharks mainly feed on teleost fish, cephalopods, and occasionally decapod crustaceans.[4] Physical traitsThey can reach lengths up to 70-88 cm (about 2.89 ft) and achieve maturity by growing to certain sizes.[5] The females mature at 63 cm and males at 54 cm.[5] Being oviparous they can produce 6-16 pups each reproductive cycle.[5] These sharks are a dark brown or black color with an even darker underbelly and markers for the caudal and pelvic fins.[2] Due to these darker markings the pelvic fin marking can be seen stretching from the base of the fin to the flank as well as a small triangular-like split near the rear.[6] Their snout and build are short[2] and their eyes are large.[5] The exterior appears rough because of the varying placement of the dermal denticles that can appear almost anywhere except on the dorsal fins.[2] They have two dorsal fins with the second fin being the larger and longer of the two.[5] This second fin also contains a second spine that curves and becomes more curved throughout their life.[6] Teeth structureThe tooth structure of these sharks can help distinguish them from other sharks as well as each other.[5] While the lower jaw of teeth shows no differences between sexes, the upper jaw does.[5] Females have been shown to have lanceolate central cusps to support their teeth.[5] Males only have central cusps in a narrow structure.[5] Species similaritiesDue to some similar morphological traits, the New Zealand Lantern shark can often be confused with the Southern Lantern shark and are thought to be connected to one another.[6] The largest piece of evidence for this connection is that both sharks have dermal denticles that are consistently conical-cusped and are randomly distributed.[6] Other evidence includes having a similar curved spine on juvenile's dorsal fin and flank markings.[6] Despite all the similarities, The Southern Lantern shark is mainly located off the South American coast as opposed to the New Zealand coast.[6] References
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