The Traveller lanternshark or Blue Eye lanternshark (Etmopterus viator) and also sometimes known as the Slate lanternshark is a sharkbelonging to the family Etmopteridae. It was classified by Straube in 2011. It has been spotted off of New Zealand and South Africa. You can read the full description below.
Family: Etmopteridae – Lantern Sharks
Genus: Etmopterus
Species: viator
Phylum– Chordata
Class– Chondrichthyles
Subclass– Elasmobranchii
Common Name– Dogfish Sharks
Family– Etmopteridae
Common Name– Lantern Sharks
Genus– Etmopterus
Species– viator
Status: IUCN Red List NOT EVALUATED
Average Size and Length: Their typical length is between 46-50 cm/1.5-1.6 feet. Males have been recorded at 39.1 cm/1.3 feet, and females at 57.7 cm/1.9 feet.
Teeth and Jaw: The mouth is strongly arched and broad 0.4 (0.11-0.43) % of the head length, with dignathic homodont dentition. The upper teeth are multicuspid with two lateral pairs of cusplets flanking a main cusp. The lateral cusplets are smaller than the central cusp. Most males have, at least in the majority of the upper teeth, only one pair of cusplets. The lower teeth are single-cusped and interlocking. There are seven tooth rows in the upper jaw with three functional rows and four replacement rows. The lower jaw has one functional tooth series and three replacement rows. There are 26 teeth in the upper and 37 in the lower jaw. There are no symphyseal teeth.
Head: The head is long 0.21 (0.21-0.26) % of the total length and broad 0.1 (0.1-0.15) % of the total length. The snout is short 0.41 (0.40-0.46) % of the head length, and broad 0.37 (0.34-0.38) % of the head length. The interorbital distance is narrow 0.28 (0.26-0.36) % of the head length, which is shorter than the snout width. There are large oval eyes. The eye length is 0.26 (0.19-0.26) % of the head length. The eyes shine or reflect a greenish hue in fresh specimens. There are large tear-drop shaped spiracles 0.05 (0.03-0.08) % of the head length. The nostrils are large and oblique 0.11 (0.11-0.15) % of the head length.
Denticles: The dorsal fins are densely covered with dermal denticles. The caudal fin and upper and lower lobes are widely covered with dermal denticles.
Tail: The caudal peduncle is short 0.1 (0.09-0.1) % of the total length. There is a large heterocercal caudal fin 0.2 (0.19-0.21) % of the total length, with strong upper and weaker lower edged lobes.
Demographic, Distribution, Habitat, Environment and Range: The Traveller lanternshark or Blue Eye lanternshark is found in the northern part of the Kerguelen Plateau, off New Zealand and South Africa. It has been confirmed to be present at the Macquarie Ridge. Marin benthopelagic; depth range 2,723-4,593 feet.
Aesthetic Identification: The body of the Traveller lanternshark or Blue Eye lanternshark is fusiform shape. The gill openings have distinct white margins.There is a moderately long interdorsal distance 0.19 (0.17-0.24) % of the total length. It is a very long distance from the first dorsal fin spine insertion to the snout tip 0.36 (0.36-0.43) % of the total length. Pectoral fins are rounded and white-edged with fringed ceratotrichia and are moderate in size. The inner margin is 0.04 (0.04-0.06) % of the total length. The fin base is short 0.05 (0.03-0.06) % of the total length. The second dorsal fin is significantly larger than first dorsal fin. The height is 0.09 (0.10-0.15) % of the total length, compared to 0.03 (0.03-0.05) % of the total length in the first dorsal fin. The second dorsal fin is deeply concave with a drawn-out lower lobe. Both dorsal fins are fringed, with strong fin spines. The second dorsal fin spine is larger than first (which was broken in the holotype) pointing posteriorly. The first dorsal fin originates distinctively behind the pectoral fin insertions, whereas the origin of the second dorsal fin is only slightly behind the pelvic fin insertions.
Biology and Reproduction: The vertebrae count is 75 – 84. The reproduction of the Traveller lanternshark or Blue Eye lanternshark is ovoviviparous. They give birth to between 2-10 pups per litter. Males reach sexual maturity around 46 cm/1.5 feet, and females around 50 cm/1.6 feet.
Behavioral Traits, Sensing and Intelligence: Unknown.
Traveller Lanternshark or Blue Eye Lanternshark Future and Conservation: Not enough data to evaluate.
Traveller Lanternshark or Blue Eye Lanternshark Recorded Attacks on Humans: Not a threat to humans.
Straube, N.; Duhamel, G.; GaSco, N.; Kriwet, J.; Schliewen, U.K. (2011). “Description of a new deep-sea Lantern Shark Etmopterus viator sp. nov. (Squaliformes: Etmopteridae) from the Southern Hemisphere” (PDF). The Kerguelen Plateau: Marine Ecosystem and Fisheries, Société Française d’Ichtyologie, Paris: 135–148.