My best guess is mucoid plaque. Worms have distinctive tapers to them and they usually are cylindrical (not irregular). It is my opinion (not to be controversial), but I think that the rope worm ideas passed around are being mistaken for mucoid plaque.
Did the arrow shaped head look something like a shark fin? If so, I saw these before (under a microscope) which my best guess was juvenile roundworm. I later saw the adults come out following a treatment of using neem, myrrh, boswellia (franckincense) and enteric coated oil of oregano (NOW).