oh god oh fuck the clams desrgodthe clam s
but yes!! sorry for such a late answer. cniderians are my favs fr!! most of these facts are jellyfish-related since jellies are very peculiar cnidarians, but I have much love for anemones, polyps and hydroids as well!! I’m not as knowledgeable on cnidarians as like,, many other people lmao but here is some of my fav cnidarian facts (some horrifying and some not) as someone who enjoys marine biology recreationally
- jellyfish have an incomplete digestive system!! they have no intestines or organs that would usually be used for digestion and general body function. because of this, they use the same opening or orifice to both take in food and expel waste!! so food go in and out through the same area.
- (I believe) all cnidarians have light-sensing organs called ocelli, but box jellyfish have more advanced visual systems! they have four eye capsules, with six eyes in each!! there are upper and lower eye lenses! those dudes can See you.
- speaking of box jellies— box jellies have their own class in the Cnidaria phylum! they’re in class Cubazoa. special little guys
- some jellies have teeth!! they’re not the same as our teeth, but some jellies like comb jellies have thin, sharp hairs on their tentacles to help them catch prey. chomp chomp!
- I don’t know much about these guys myself, but there’s a kind of jellyfish that can “reverse age”— the “immortal jellyfish” can transfer its cells back to early stages of development once it reaches adulthood.
- I don’t know much abt these little guys but there’s a kind of parasite called Polypodium hydriforme (which can be classified as a cnidarian in some cases, but also can be qualified in other classes) which parasitizes sturgeon n other similar fish eggs! I would love to learn more abt them myself
^ ( the Polypodium hydriforme in question)
I’m sure there are much more weird bits of information on all kinds of cnidarians out there, but those are the ones I happen to know off the top of my head or find the weirdest. tysm for the ask! hope this satiated the need for horrifying cnidarian facts :}}