giant species sole member family widely distributed typically fine sediments upper continental slope depths species reaches length width oval pectoral fin disc long flexible broad angled snout entire half tail supports long slender leaf shaped caudal fin coloration dark white skin completely covered tiny dermal denticles crustaceans cephalopods bony fishes hunt sea floor open water probably viviparous mother supplying young milk captured rays merit caution long species taken commercial fisheries numbers small significantly threaten population assessed concern taxonomy phylogeny scientific description authored report named new species honor late director placed genus based long low caudal fin lack dorsal fin type specimens collected september near mouth mature male immature male common names species include davies giant morphological phylogenetic study concluded basal moved species genus family derived greek primitive ray subsequent morphological studies basal position disagreed relationships nearby taxa fully resolve position assigned family found sister taxon recommended placed family phylogeny better resolved authors tended preserve family distribution habitat records come number locations scattered widely south_africa northern southern coastline australia northwestern australia northeastern australia hawaii dwelling species generally inhabits upper continental slope depths muddy record deep locally common tropical australian waters description body enlarged pectoral fins forming disc usually longer wide leading margins disc converge broad angle snout thin measures times long diameter orbit snout tip slightly disc small eyes positioned ahead angular posterior large circular nostrils placed closed mouth connected pair broad grooves nostrils broad curtain skin strongly fringed posterior margin wide straight mouth contains tooth rows jaw increasing number age tooth small low blunt adult males teeth center sharp backward pointing pairs gill slits small placed beneath disc pelvic fins small blunt outer corners moderately thick tail measures long disc lacks lateral skin dorsal fins spines present atop tail ahead halfway point slender caudal fin originates short distance sting symmetrical terminates rounded leaf like shape skin densely covered fine dermal denticles sparse absent pelvic fins ventral disc margin mouth brown rays irregular darker spots underside white narrow dark border lateral disc margins tail entirely dark caudal fin black large species grows long weight southern africa known exceed long australia biology ecology diet consists cephalopods crustaceans including crabs bony fishes including long flexible snout suited sediment presence species diet suggest hunt sea floor recorded individual found severely sharks capable flesh like larger animals presumed similar viviparous having developing embryos produced milk given large size habits probably highly prolific small litter size long gestation period young apparently born close long evidenced capture free living specimen size bore yolk sac males females mature sexually long respectively maximum size likely maturation size varies geographic regions human interactions captured powerful tail violently long sting inflict injury fishery worker caught incidentally meat sold poorly regarded commercial fisheries operating range including south_africa taiwan indonesia australia extensive small numbers landed result determined species threatened human activity listed concern fisheries expand future susceptible probable rarity low reproductive rate
Deepwater stingray