slender smooth slender smooth species ground shark family endemic waters new_zealand usually found close continental slope depths extremely slim plain brownish shark reaching length slender smooth identified broad flattened head long bell shaped snout mouth angular short furrows corners contains high number tooth rows jaws dorsal fins roughly equal size diet slender smooth diverse dominated small benthic bony fishes crustaceans exhibits specialized form females produce single capsule contains develops embryo rest stores yolk material external yolk sac growing embryo mainly sustained yolk sac gestation additionally supplied milk produced mother typical litter size pups assessed slender smooth concern taken fishery great numbers furthermore large portions range minimal fishing activity taxonomy phylogeny known specimen slender smooth long adult male collected december depth cape new_zealand preserved crew curiosity given described issue scientific journal transactions royal society new zealand named species reference extremely slender body proposed separate genus slender smooth character lord rings shark bears resemblance form habits placed noted similarities false time chose maintain sole member family numerous unique traits recently increasingly tended group family arrangement phylogenetic study colleagues found genera high degree genetic similarity protein genes form natural clade apart additional species described additional species described distribution habitat range slender smooth restricted upper middle continental slope new_zealand including submarine features north kings ridge uncommon species mainly found deep recorded deep prefers temperature approximately generally swimming near sea floor shark inhabits soft rocky habitats terrain ranging steep slopes description slender smooth thin body broad highly flattened head snout long distinctive bell shaped outline viewed eyes horizontal oval shape equipped rudimentary membranes protective beneath eye prominent ridge smaller nostrils preceded small triangular flaps skin line mouth forms angle short furrows mouth corners upper lower jaws contain rows respectively small closely spaced teeth tooth narrow upright central flanked smaller sides pairs gill slits short pectoral fins originate fourth gill gently curved margins pelvic fins small angular males pointed dorsal fins similar size shape narrowly rounded concave trailing margins dorsal fin originates rear pectoral fins second dorsal fin originates pelvic anal fins ridge present dorsal fins anal fin half high dorsal fin nearly straight trailing margin short narrow caudal fin makes sixth total length lower caudal fin lobe indistinct upper lobe strong ventral notch near tip skin densely covered small overlapping dermal denticles crown mounted short stalk bears horizontal ridges leading marginal blade like teeth central tooth particularly long species plain brownish gray lighter grows long weight females reaching slightly larger size males biology ecology slender smooth likely schooling species variety benthic fishes invertebrates human garbage reported stomach contents small bony fishes particular important prey type followed crustaceans cephalopods stars sharks fish egg consumed challenger plateau cephalopods important food source juveniles long like false slender smooth exhibits form different sharks mature females single functional right functional embryo develops time resulting litters rarely pups inner surface covered packed single rigid amber colored capsule develops embryo remaining begin break embryo transfers yolk material external yolk sac serves main source gestation process completed length embryo receive secondary nutrition form milk produced mother embryo long emerges capsule time translucent gelatinous embryos long developed external gill external yolk sac entirely absorbed embryo long close born males females reach sexual maturity approximately long human interactions harmless humans economic value slender smooth occasionally caught incidentally northern range lies little waters listed concern shark low render susceptible population fishing pressure increase future
Slender smooth-hound