Etmopterus viator Straube, 2011

Family:  Etmopteridae (Lantern sharks)
Max. size:  39.1 cm TL (male/unsexed); 57.7 cm TL (female)
Environment:  bathydemersal; marine; depth range 830 - 1400 m
Distribution:  Southern Ocean: Northern part of the Kerguelen Plateau, off New Zealand and South Africa. Further confirmed for the Macquarie Ridge (P. Last, pers. comm.). It hypothetically occurs in the whole Southern Hemisphere (Ref. 87779).
Diagnosis:  Vertebrae: 75-84. A medium-sized Etmopterus species with the following combination of characters: body fusiform, caudal peduncle short 0.1 (0.09-0.1) % of total length (TL). Moderately long interdorsal distance 0.19 (0.17-0.24) % TL, very long distance from first dorsal fin spine insertion to snout tip 0.36 (0.36-0.43)% TL. Head long 0.21 (0.21-0.26) % TL and broad 0.1 (0.1-0.15) % TL long, as long as caudal peduncle. Snout short 0.41 (0.40-0.46) % head length (HL) and broad 0.37 (0.34-0.38) % HL. Interorbital distance narrow 0.28 (0.26-0.36) % HL, shorter than snout width. Large oval eyes, eye length 0.26 (0.19-0.26) % HL. Eyes reflect greenish in fresh specimens. Large tear-drop shaped spiracles 0.05 (0.03-0.08) % HL. Mouth strongly arched and broad 0.4 (0.11-0.43) % HL with dignathic homodont dentition . Nostrils large and oblique 0.11 (0.11-0.15) % HL. Gill openings with distinct white margins. Pectoral fins rounded and white-edged with fringed ceratotrichia, moderate in size. Inner margin 0.04 (0.04-0.06) % TL, fin base short 0.05 (0.03-0.06) % TL. Dorsal fins densely covered with dermal denticles, 2nd dorsal fin significantly larger than 1st dorsal fin, height 0.09 (0.10-0.15) % TL compared to 0.03 (0.03-0.05) % TL in 1st dorsal fin. 2nd dorsal fin deeply concave with drawn-out lower lobe. Both dorsal fins fringed, with strong fin spines. The 2nd dorsal fin spine is larger than 1st (broken in the holotype) pointing posteriorly. First dorsal fin originate distinctively behind the pectoral fin insertions, whereas origin of 2nd dorsal fin only sligthly behind pelvic fin insertions. Large heterocercal caudal fin 0.2 (0.19-0.21) % TL with strong upper and weaker lower edged lobes, widely covered with dermal denticles (Ref. 87779).
Biology: 
IUCN Red List Status: Least Concern (LC); Date assessed: 27 June 2017 Ref. (130435)
Threat to humans:  harmless


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