species electric ray family endemic southeastern australia common ray inhabits shallow continental shelf waters southern portion range deeper continental slope waters northern portion range prefers sand mud habitats species identified shaped pectoral fin disc concave anterior margins long tail developed skin plain dark brown dorsal maximum known length dwelling feeds mainly worms crustaceans produce moderate electric shock defend predators species gives live birth young sustained term yolk litter size ranges common fisheries population appear threatened human activity assessed concern taxonomy phylogeny scottish naturalist described contribution london classifying new species genus gave specific epithet female long collected port arthur tasmania richardson noted ray known locally ground shark common names species include electric ray electric torpedo little phylogenetic study based mitochondrial dna found belonging different lineage giant electric ray description reaching length shaped pectoral fin disc short blunt snout concave leading margins medium sized eyes followed smaller nearly circular smooth pair large electric organs located head curtain skin nostrils posterior margin narrow highly mouth encircled deep groove teeth small diamond shaped pointed tips arranged pattern bands remain exposed mouth closed pairs gill slits beneath disc triangular pelvic fins longer wide adult males extend past pelvic fin rear tips broad flattened tail quarter longer disc bears prominent skin sides dorsal fins roughly equal size shape originating rear tips pelvic fins tail terminates low caudal fin upper caudal fin lobe somewhat angular especially adult males lower lobe rounded skin bears devoid dermal denticles plain dark brown lighter fins underside white dark juveniles exhibit darker stripe darker disc dorsal fin bases distribution habitat common southeastern australia range extends harbour new_south_wales western australia encompasses tasmania tasmania found waters depth continental shelf northerly waters inhabits upper continental slope depths dwelling species sandy muddy substrate encountered vicinity rocky reefs mature rays sexes appear live apart juveniles biology ecology fairly inactive species spends long periods time buried sediment feeds primarily worms particularly family crustaceans including consumed rare occasions juvenile rays consume crustaceans roughly equal proportions adults consume shift reflect increasing experience age animals difficult locate capture crustaceans like members family defend modest electric shock predators include shark parasite species reproduction viviparous developing embryos term yolk females bear litters pups average measure long males females attain reproductive maturity lengths respectively human interactions frequently caught incidentally australia operate range discarded capture unknown probably high rate survival species appear threatened human activity listed concern
Tasmanian numbfish