Does a Photo Show a Parasite That Replaced a Fish’s Tongue?


It appears like one thing from a horror flick. A small, parasitic creature swims into the mouth of a fish and attaches itself to the organism’s tongue — sure, fish have tongues — inflicting it to slowly degrade earlier than latching onto the stub leftover, thus changing into a parasitic pseudo tongue. Over time, the host loses its capability to eat and slowly succumbs to hunger.

So claims a now-viral Instagram submit that was shared in March 2021 by the Smithsonian Institute in appreciation of #ParasiteWeek2021. And if the picture was sufficient to provide the heebie-jeebies, then chances are you’ll not wish to proceed studying. Because each the {photograph} in query and the supposed parasite featured in it are, in reality, actual.

The image featured an organism often known as a cymothoid isopod and was initially shared on Aug. 3, 2020, by marine biologist Jimmy Bernot, a post-doctoral scholar with the National Science Foundation and Smithsonian’s National Museum of Natural History specializing in crustacean phylogeny and parasite evolution. In an electronic mail to Snopes, Bernot mentioned that he captured the picture throughout a 2016 survey of fish parasites of Moreton Bay, Australia. 

The host fish is thought scientifically as Mugil cephalus or the Flathead mullet. 

“Not to be confused with the business in the front, party in the back haircut,” mentioned Bernot. 

And the parasite seen contained in the mullet’s mouth is what is called a cymothoid isopod that measured about an inch lengthy. According to the scientist, it appeared that the fish did use the creepy-crawly as a “pseudo tongue.” 

The truth which you can see imprints of the fish’s tooth on the again of the isopod signifies the fish is crushing objects towards the isopod just like how the fish would use its tongue, he mentioned.

Jimmy Bernot

Isopods are marine invertebrates, or animals with out backbones, that belong to a higher group of animals known as crustaceans. Only a handful of the no less than 95 identified households of isopods are parasitic, considered one of which being cymothoid, in keeping with analysis printed in a 2014 challenge of the International Journal for Parasitology: Parasites and Wildlife. The cymothoidae household specifically is made up of 350 species of aquatic parasitic isopods. Widely distributed world wide in each oceanic and freshwater habitats, cymothoids are on the bigger facet of parasites and might attain lengths upwards of a quarter of an inch, with the most important reaching lengths of as much as 3 inches.

“Cymothoids superficially look like free-living isopods, such as terrestrial rolly-pollies or pillbugs that people may be familiar with, except for their powerful hooked legs that they use to attach to their host,” defined Bernot. “As adults, they are not good swimmers and typically stay permanently attached to their host.”

Equipped with a lengthy, slender physique that tapers on the finish and sharply curved hooks on the finish of its limbs, the cymothoid can connect to its host fish on the gills or mouth in addition to externally or contained in the host flesh, relying on the species. Cymothoids are typically host-specific, that means every cymothoid sometimes attaches to a single host species or a small group of associated fish. On a parasitized fish, Bernot mentioned that there’ll typically be a single giant feminine and a few small males hooked up close by on the identical fish.

Various sorts of parasitic attachment methods of cymothoid isopods. International Journal for Parasitology: Parasites and Wildlife

Only a few species connect particularly to the tongue, and these are generally known as “tongue-biters.” Other species connect to the pores and skin or gills, however all have detrimental results on their hosts together with blood loss because of the parasite feeding, pores and skin and tissue harm, deformities, and total stunted development and reproductive points. 

And in the case of the cymothoid featured on social media posts, the Smithsonian Institute wrote that the “crustaceans sever the host fish’s tongue” — a declare that’s solely partly true.

“The cymothoids feed on blood and perhaps some of the tongue and surrounding tissue in the host’s mouth, but the loss and degradation of the tongue are at least partially, if not mostly, due to atrophy of the tongue from mechanical damage caused by the strong, hooked legs that the isopod uses to attach to the base of the tongue,” mentioned Bernot.  In brief, cymothoids don’t snip straight via the tongue of the fish, however relatively trigger such harm that a portion of the tongue can finally fall off. 

And in keeping with the analysis establishment, Bernot’s {photograph} is the one identified occasion within the animal kingdom the place a parasite has been noticed as totally changing its host’s organ. In a reply to his authentic submit, Bernot mentioned that the pictured cymothoid isopod holding triggered its host to atrophy — a fancy phrase for losing away.

Studying parasites like cymothoids helps researchers to raised perceive evolutionary biology and the distinctive variations that particular person species receive with a purpose to survive. 

“It appears different groups of parasitic isopods have independently evolved strongly clawed legs through a process called convergent evolution,” mentioned Bernot. “Convergent evolution is of interest to evolutionary biologists and developmental biologists since it gives us insights into how evolution can shape the morphology of animals.” 

And cymothoids additionally influence human well being and economies due to their impact on fish, which Bernot mentioned may typically infect greater than 90% of fish on a single farm, together with commercially farmed sea bass, bream, and salmon. As gross as it might sound, consuming a fish with a parasite is “definitely still safe for humans,” however the fish is perhaps smaller or have scars, and Bernot mentioned meaning it could actually’t be offered at its highest market worth.




Leave a comment