giant freshwater giant freshwater widely known junior synonym species family found large rivers borneo historically widely distributed south southeast_asia largest freshwater fish world species grows upwards reach weight relatively thin oval pectoral fin disc widest sharply pointed snout protruding tip tail thin whip like lacks fin species uniformly grayish brown white underside pectoral pelvic fins bear distinctive wide dark bands posterior margins dwelling nature giant freshwater inhabits sandy muddy areas small fishes invertebrates females live birth litters pups sustained term produced milk species faces heavy fishing pressure meat recreation display extensive habitat degradation forces resulted substantial population declines central thailand result assessed giant freshwater endangered taxonomy phylogeny scientific description giant freshwater authored dutch volume journal van account based juvenile specimen collected indonesia named new species greek scales assigned genus synonym subsequent years description largely overlooked giant freshwater described issue gave came widespread usage peter confirmed refer species published earlier scientific giant freshwater species called giant freshwater giant freshwater complex similar freshwater southeast_asia tentatively identified australian freshwater described separate species freshwater new_guinea probably confirmation study india described closely resembles hand comparison freshwater dna acid sequences india thailand revealed significant differences finally additional research needed assess degree divergence populations inhabiting drainage basins distribution determine taxonomic terms broader evolutionary relationships giant freshwater rest family phylogenetic analysis based mitochondrial dna reported closely related ray turn formed clade finding adds growing consensus genus description giant freshwater thin oval pectoral fin disc slightly longer wide elongated snout wide base sharply pointed tip projects disc eyes minute widely spaced large nostrils short curtain skin finely fringed posterior margin small mouth forms gentle arch contains seven large center small sides floor small rounded teeth arranged pavement like bands pairs gill slits ventral disc pelvic fins small thin mature males relatively large thin cylindrical tail measures times long disc lacks fin single spine positioned upper surface tail near base long spine largest species band heart shaped upper surface disc extending eyes base sting row enlarged center disc remainder disc upper surface covered tiny denticles tail covered sharp past sting species plain grayish brown yellowish pinkish fin margins life skin coated layer dark brown underside white broad dark bands edged small spots trailing margins pectoral pelvic fins tail black spine giant freshwater reaches width length likely grow larger reports individuals weighing ranks largest freshwater fishes world distribution habitat giant freshwater known inhabit large rivers associated borneo occurs potentially far upstream thailand borneo species found reportedly common caught reported surveys past years found region recent river surveys java recorded presence despite island locality species historical records india similarly recent accounts populations giant freshwater separate river probably isolated species occurs environments evidence crosses marine waters dwelling species favors sandy muddy habitat unexpectedly found near heavily populated urban areas biology ecology diet giant freshwater consists small fishes invertebrates crustaceans detect individuals seen edge river possibly feeding parasites documented species include giant freshwater viviparous developing embryos initially yolk later milk provided mother species appear migrating fresh salt water complete life cycle observed litter sizes range pups measure pregnant females frequently found serve nursery areas males mature sexually approximately female maturation size life history details unknown human interactions giant freshwater aggressive merits caution sting toxic capable piercing bone range species caught incidentally lesser extent fish traps difficult time consuming catch hooked ray bury large quantities mud impossible lift drag boats substantial distances underwater meat large specimens cut kilogram pieces sale adults food killed regardless giant freshwater increasingly targeted sport display public trends pose conservation concerns catch release universally practiced post release survival rate unknown species survive captivity major threats giant freshwater habitat degradation resulting land development construction dams fragments population reducing genetic diversity increasing resulting extinction low reproductive rate giant freshwater pressures central thailand population estimated reduced past years declines severe locations size rays caught decreased significantly example average weight landed ray dropped status populations areas borneo largely unknown result documented declines assessed species endangered overall critically endangered thailand 1990s thai government initiated captive breeding program bolster population freshwater species issue habitat degradation program hold
Giant freshwater stingray