it is a species from family Dasyatidae (stingrays). What is the species - it depend on area where this individuals was caught. Check here - http://www.fishbase.se/identification/specieslist.php?famcode=20&areacode=
And as far as I see the tail of this was cutted, isn't it?.
I agree with the previous suggestions that this looks like H. uarnak. However it is important to note that this is a species complex, and the taxonomic divisions within it are still be elucidated.
Our above colleagues are right. Its more of the Himantura uarnak also found here in the waters of Palawan, Philippines. Recorded in Sulu Sea in the 80's. It is still recorded in Palawan waters till 2000. It belongs to Family Dasyatidae. Common English name: Honey Comb Stingray. It is hunted for food in Palawan, but it is also a good material for export to Japan for materials that has something to do with "Kendo" sport. Capture of this species is prohibited in the Philippines.