Animal Eyes | Bigeye Thresher Shark | Type of Bigeye Thresher Shark, Alopias superciliosus, ranks 10th in the world's largest shark species. Bigeye Thresher shark species can be found in the equatorial ocean regions of the world and can be found at a depth of 1650 feet on the seabed. Bigeye Thresher Shark has a characteristic purplish gray and short lives of 15.1 feet and reach up to 795 lbs (360.60 kg).
In Latin the species are known as alopex, meaning fox. This has translated into many languages, English as well, as thresher sharks are sometimes called fox sharks. The common name thresher shark is derived from the distinctive caudal fin or thresher-like tail, which can be as long as the body of the shark itself.
By far the largest of the three species is the common thresher shark, that can reach a length of 6.1 metres and a weight of around half a ton. The bigeye thresher is next in size, reaching a length of 4.9 m; at just three meters, the pelagic thresher shark is the smallest. Only the pelagic thresher shark can be seen while diving at Monad Shoal. Unsubstantiated reports by local divemasters of bigeye sigtings surface from time to time, but no photographic evidence support this. In any case, if they do appear, it a very rare indeed.
Apart from the Bigeye thresher, these sharks have relatively small eyes positioned to the forward of the head. Apart from the eyes, the three kinds can often be told apart by the colour of the dorsal surface of the body. Common threshers are dark green, bigeye threshers are brown and pelagic threshers are generally blue. Lighting conditions and water clarity can of course affect how a shark appears, but the color test is generally supported when other features are considered.