Caption London - Arabstoday It was the most exhausting and dangerous catch of his career. When British angler Jeremy Wade decided to grapple with one of the world's biggest and deadliest freshwater fish he never imagined he would win the battle. But the 53-year-old managed to snare the 20 stone monster short-tailed stingray in Argentina after a tiring four hour standoff on the River Parana near Buenos Aires. After taking his bait of eel, the creature stuck itself to the bottom of the river, prompting an exhaustive battle of attrition with Mr Wade, host of the TV series River Monsters. The flat fish is one of the heaviest found in the world's freshwater rivers and has been known to kill people with its lethal and poisonous barb. The four hour stalemate was only broken when the fish became tired and Mr Wade was finally able to lift it towards the surface. Even then he had to tow it towards the shore using his boat before he could see the huge fish in all its glory. Mr Wade, from Bath, Somerset, had to wear a pair stab-proof gloves while he handled the creature which was then released back into the water safe and well. He said: 'This is the largest true freshwater fish that I have ever caught. 'This species is the biggest true freshwater fish in the world and this must be one of the biggest of the species. 'It just stuck to the bottom and borrowed itself in the sand and the mud, so it was like lifting a dead weight. 'After half an hour with no further movement I was convinced it had swum around a tree. 'We moved position and I pulled my rod from a different angle. When I locked the reel with my thumb and heaved and I felt a wrench on the line. 'Then it was stalemate again. For the next two hours nothing changed then I gave it another desperate heave and got it moving. 'It eventually got tired and when it lifted off the bottom we pulled it into shallow water. 'It was a huge circular shape, humped in the middle and the same colour as the sand. 'My ams and back were completely shot afterwards, I was so tired.' Because the short-tailed ray - Potamotrygon brachyura in Latin - is camouflaged to sand unwary people often tread on them in shallow water. When the fish attack it lashes out with its lethal tail which is covered in thorny spines that can rip flesh to the bone. It has two barbed four inch prongs which can inject a flesh-rotting venom. Mr Wade said: 'If you get the barb through an artery or body cavity it can be fatal. It normally attacks feet and ankles from where people tread on them by accident. 'It can leave a nasty wound and take six or seven years to stop weeping. People in that area of Argentina shuffle their feet forward when walking through the surf so that they kick the side of it and not tread on top of it.'