#hexanchiformes

You may not know this but im a huge fucking nerd

Not yet!

most sharks have two dorsal fins, but not all!! such as

order Hexanchiformes, with 6 species: frilled sharks (2), sixgill sharks (2), and sevengill sharks (2)

I got to see a very close relative of my favorite shark; the Bluntnose Six-Gill. I saw the Broadnose sevegill!! Seeing one was so exciting!! They are literally prehistoric babies :3 A fun fact about the Broadnose sevengill is that they’re the only extant member of the genus Notorynchus. Notorynchus is a genus of deep water sharks.

Today's shark is the frilled shark!

The basics: the frilled shark (Chlamydoselachus anguineus) is a poorly-understood, primitive species of shark in the order Hexanchiformes (along with the six- and seven-gilled sharks and one other and even more poorly understood frilled shark species, the south African frilled shark). They are often considered a "living fossil" species thanks to traits resembling more basal species of shark, including a long, eel-like body, more than five gill slits (they have six), a quasi-cartilaginous notochord, and jaws that are articulated to their skull. They appear unchanged in the fossil record as early as 150 million years ago!

Conservation status: least concern. Frilled sharks were once classified as near-threatened thanks to their slow reproduction rates and risk of food depletion in their habitats thanks to over-fishing, but have been re-assessed as a species of least concern. They are naturally uncommon sharks and are occasionally bycatch of deepwater trawl lines.

Today's fun fact: frilled sharks have unique, trident-shaped teeth, and they are likely not only practical for eating but also for hunting! Frilled sharks likely swim with their mouths open, and the bright white teeth in the darkness of the open ocean lures prey right into their mouths!

Hexanchiformes. This order of sharks are the most primitive morphologically. It includes the cow shark.

Squatiniformes. This order is made up of the angelsharks, which have flattened bodies and broad pectoral fins, and are bottom-dwelling ambush predators