Could my irridescant shark have been eaten or what??

I have two tinfoil barbs, two blue spot gouramis, two black skirt tetras (yes I know I need to get more) and a plecostomus. As of late, I also had an irridescant shark. Yesterday morning, I woke up and looked in my tank and he's gone. I checked under ever ornament, every plant, and even in the filter. I have a hood, so he could not have jumped out. There are NO remnants to be found. He's just dissapeared. Who could have eaten him?