australian shark australian shark uncommon species ground shark family inhabits shallow waters northern australia depth smaller sharks frequent sand habitat shift coral reefs grow older slim species reaching length shaped fins dark tips second dorsal fin caudal fin upper lobe upper teeth broad strong trailing edge lateral line prominent exhibits downward curve second dorsal fin feeding exclusively cephalopods australian shark hunts near sea floor viviparous developing embryos connection born month gestation period species productive shark females bearing litters pups usually twice year australian shark caught lesser extent fisheries numbers population threatened listed concern taxonomy originally regarded shark australian shark documented potentially distinct species scientific description authored peter volume scientific journal gave specific epithet basis range designated type specimen adult male long caught depth western australia description reaching length australian shark slender shaped body moderately long head thick rounded snout large oval eyes possess membranes posterior tiny located eyes large nostrils preceded fairly long triangular flaps skin short curved mouth bears prominent furrows corners upper lower tooth rows visible mouth closed upper teeth broad angled large trailing edge lower teeth thin upright smooth edges pairs fairly short gill slits fins particularly narrow pectoral fins shaped degree medium sized dorsal fin originates pectoral fin rear tips second dorsal fin thirds tall ridge running pelvic fins broad slightly larger anal fin anal fin strong notch trailing margin positioned slightly second dorsal fin caudal bears crescent shaped notch upper origin caudal fin caudal fin developed lower lobe long narrow upper lobe ventral notch near tip prominent lateral line curves downward second dorsal fin skin densely covered small overlapping dermal denticles bears horizontal ridges leading marginal teeth species light grey bronze tips second dorsal fin upper caudal fin lobe indistinct larger sharks pale underside white dorsal fin pale trailing margin distribution habitat australian shark inhabits continental shelves northern australia western australia heads new_south_wales additional records unconfirmed naturally uncommon species tends swim close sea floor found waters deep juveniles small adults generally found sandy areas cover large adults occur coral reefs biology ecology australian shark feeds predominantly removing arms increasingly important diet age sharks long eat increasing accompanied habitat shift coral reefs serve reduce competition older younger individuals represent minor secondary food source particularly smaller sharks addition cephalopods mud crabs rarely consumed species probably hunts dawn dusk typically seeks dwelling prey rise water column opportunity presents seasonal broad squid known parasites australian shark include like members family australian shark viviparous developing embryos sustained connection mother mature females single functional functional gestation period months long typically litters produced annually february september litter size varies pups average embryos lose external gills length developed length born length males females reach sexual maturity approximately long respectively human interactions harmless humans australian shark commonly caught fish operating northern australia smaller numbers captured species relatively high reproductive rate losses fisheries severe affect population assessed concern
Australian weasel shark