Dear colleagues,
I received new message from one of my friends as follows:
" I was gutting and separating the loins of a skip jack tuna to cook for dinner and found a pair of parasitic worms. It burrowed just beneath the skin on the lower loin just below the Center line next to the pectoral fin (see photo).
I didn’t measure its cross section length but I believe it is 1 – 2mm but the length of one of them is 82 cm. The body appears to be segmented and feels like spiky when I hold on to it. I believe it needs to be spiky. I ran my hand down the body and it’s kind of segmented and possibly spiky (for attachment to surface while moving and feeding).
Attach photos of the worm and where found on the fish.
The fish was brine frozen at -12 deg. Celsius.
Can anyone say more on this to assist in identifying what type of worm is it?"
(Pictures belong to Mr. Anthony Ele)
Your valued answer would be high appreciated.
Kindly regards
Although both images were not so clear, but depending on the brief description, the worm may represent plerocercoid of the fish tape worm, Diphylobothrium latum. Try to provide us with an image of its scolex "the head" which is so important in its identification.
I also agree with Dr. Mhaisen, probably D. latum. Scolex characteristics are important to identify it: size: 2 to 3 mm in length × 1 mm wide; Almond-shaped or spatulate; 2 suckers; Grooves appearance; Does not have a rostellum or hooks. Deep grooves (suckers) are located dorsally and centrally on the scolex, but often appear to be lateral.
It could also be a didymozooid trematode as I believe some can get quite large and live entwined as pairs in the musculature of their host. However, most do not have this form. Nonetheless, see for example Nematobothrium, Nematobothroides and perhaps Nematobibothroides. I'm not sure about the taxonomic status of the latter genus as I only found reference to the latter in Noble and Noble's wonderful Parasitology textbook. However, they found on that was several meters long in Mola mola, and the others can get 1-2m in length.
They have been reported from tuna and there is a recent description of one from skipjack, but it is not like the one in your photos.
- Badges
- Science topic
- Similar topics
- Biological Science
- Zoology
- Ornithology