"The speartooth shark (Glyphis glyphis) is an extremely rare species of river shark, belonging to the family Carcharhinidae. It inhabits coastal marine waters and tidal reaches of large tropical rivers in northern Australia and New Guinea. Adults grow to about 2.6 m (8.5 ft) long."
"Extremely rare like other river sharks, its global population has been estimated to number no more than 2,500 mature individuals, with no more than 250 in any subpopulation."
"Furthermore, in Australia, it has been listed as critically endangered on the 1999 Commonwealth Environment Protection and Biodiversity Conservation Act, though this is of minimal effect as commonwealth protection does not apply until a distance of three nautical miles from the coast, likely outside the range of this shark."
From the wiki
What an interesting species. Would love to see an 8.5 feet one.