Everyone knows about great whites, hammerheads and tiger sharks, but what about those lesser known species, that are just as cool? With over 440 species of sharks, it’s easy to get sidetracked by the more (in)famous species, so I’ve listed my top 5 lesser-known shark species, just for your pleasure.
Very little is known about this elusive species and when it was discovered in 1976 it was so different from all the other known shark lineages, a new one was created – Megachasmidae. Despite its 50 rows of hook-like teeth, this species is a filter-feeder, like whale and basking sharks, so don’t be fearful. You’ll be lucky to even see one! Although megamouths are a cosmopolitan, wide-ranging species, only 55 confirmed sitings have been made since it’s discovery. They’re not the best swimmers either, with pectoral fins smaller than their heads. One of the coolest things about this shark is that it’s a vertical migrant across 24hr cycles, swimming closer to the surface as the sun goes down. Oh, and it’s also the most primitive lamniform shark that we know of today!
Dwarf Lantern Shark
The smallest shark in the ocean! Well, at least from what we know right now. Like other sharks on this list, very little is known about this species. They have been observed up to 1,440ft below sea level off the coast of South America, on the upper continental slopes off Columbia and Venezula. Like many other organisms living at these deep depths, dwarf lantern sharks make use of bioluminescence. Known as the ‘tiny shark that glows’, these guys have photophores that they use to help them diguse themselves from predators whilst feeding on krill in the water column. Other species of lantern shark, include the broadbanded lantern shark and the velvet belly lantern shark.
Endemic to the coast of South Africa and a small species of catshark, these guys are considered near-threatened on the IUCN Red List. Covered in longitudinal stripes this shark is reminiscent of striped pyjamas and mainly resides in kelp forests or rocky reefs, helping to camouflage it from larger predators. You may have seen these guys in aquariums, as they tend to adapt well to a captive environment.
Another extremely rare species is the speartooth shark, also known as the Bizant river shark. These guys were first tagged by researchers back in 2015. What’s interesting the most to me about this species, is that it is one of only five known freshwater sharks. Speartooths inhabit the rivers of northern Australia and New Guinea. With so few sightings recorded and only a few immature specimens ever found, it is hard for scientists to predict an accurate estimate of population size, but it is thought that there are only roughly 2,500 individuals. With pressures from habitat loss and being caught as bycatch by local fishermen, the IUCN Red List has categorised the speartooth as an endangered species.
Cookie Cutter Shark
This shark gets its name from the cookie cutter-like manner it takes a bite out of its prey – although the shape left is more conical. Like the dwarf lantern shark mentioned above, this little guy also uses bioluminescence, with its entire underside covered in light-emitting photophores. Despite their arguably cute appearance, cookiecutters have been known to bite humans and have even reportedly taken bites out of nuclear submarines. Don’t worry though, cookiecutters are small sharks, reaching up to only 22 inches in length and as a species they generally rare to find.
Much more research is required into these elusive shark species, as well as the majority of more well-known species. For example, we still are unsure of where Great Whites go to breed. Behavioural ecology and population analyses are just two of the crucial elements of research that are required so we can figure out how best to conserve these fantastic creatures. Some species, like the speartooth listed here, may become extinct before we even get a chance to properly study them. Who knows, maybe you’ll be the person to find out.
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If you’d like to find out more about sharks and the ways you can help conserve their future, I’d recommend checking the following organisations out:
N.B. I do not own these images.