Help identiftying large intestinal worm/parasite

Can someone identify this parasite.

I did the mistake of tearing it open before taking pictures.

But let me tell you, this thing was built like a tank.
Very tough, thick, rubbery skin (which was difficult to rip open)- kind of like caoutchouc.
Clearly has a head/mouth, pointy little tail, about 5" long (more or less)









If I had to guess I would say it's some kind of roundworm, but I am unsure maybe it is a trematode...

If you have any clues please let me know - it will be very much appreciated to get some opinions.