#sixgill sawshark | Explore Tumblr posts and blogs

quark-nova · 2 years ago

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Sometimes I see you on my dash doing a science and it makes me happy and do you have any shark facts pls? Sharks are so cool. Especially the weird deep sea sharks that always get ignored when ppl talk about great whites and such (no shame to great whites they are very lovable,)

Of course I have quite a lot!

Okay so we can start with the first shark ancestors, the spiny sharks! They lived in the Silurian, more than 400 million years ago. They looked pretty unique as each fin was actually a spine supporting the whole fin, and had already reacquired the cartilaginous skeleton that modern sharks have!

Nobu Tamura / CC BY-SA 4.0

They often had a bunch of little pairs of "finlets" (not real fins, but spines serving a similar purpose) between their actual fins! So spiky!

Then we come to the true sharks (and rays). Or, nearly. Turns out, there are two main groups of shark-like cartilaginous fish alive today. On the one hand the sharks and rays, and on the other hand the chimeras, majestic creatures often found in the deep sea!

Havforskingsinstituttet / CC BY-SA 4.0

Turns out however, the ancestors of chimeras were historically way more shark-like! And ranged between adorable and pretty weird, and more often than not both! Here's one of them: the sawblade shark, Helicoprion!

Entelognathus / CC BY-SA 4.0

And here's the anvil shark!

DiBgd / CC BY-SA 4.0

And the wtfshark, Squaloraja!

Nix Illustrations / I don't know the license but he's on Tumblr

And now we can move on to the actual sharks. And rays. And sawsharks. And sawfish. And sawskates. The design so good they had to invent it thrice.

Here's a sawfish (these ones are closer to rays!), heavily judging whoever took the photograph. Surprisingly, they're the largest of the bunch, reaching up to 7 meters - while sawsharks are barely a meter in length at best, and sawskates aren't alive anymore but could reach a respectable 4 meters! (although they were wider relative to their size, which has to count for something?)

Simon Fraser University - University Communications / CC BY 2.0

Now that we saw the saws, we can move on to actual sharks... wait what's that? An interruption by the coolest species of six-finned ray?

Robert Fisher, Virginia Sea Grant / CC BY-ND 2.0

Seems like it. Of course I had to mention my favourite cartilaginous fish in the bunch. Cownose rays (and their manta ray cousins) are the only vertebrates to have developed an entire new pair of fins - on their face, to help them grab stuff! Since fish paired fins are homologous to our limbs, it would be like having an extra pair of arms coming from our face!

Robert Fisher, Virginia Sea Grant / CC BY-ND 2.0

Back to sharks now (finally)! And speaking of stuff it's rare to have six of, what about sixgill sharks?

No author information / Public domain

The most divergent group of true sharks alive today, the deep-sea creatures that we call frilled sharks are actually very derived, despite their prehistoric appearance! Ironically, their more ordinary-looking sixgill cousins, the cow sharks, are more representative of how sharks started off back in the days!

NOAA / Public domain

Still six gills because why not. Or even seven, because really, why not.

Next step on our shark list (and back to the regular five-gill pattern), the angelsharks! Or sand devils, because they really couldn't decide on these ones. Angels or devils, they're absolutely adorable pancakes.

Nick Long / CC BY-SA 2.0

Now, we would still have five more orders of sharks to go, but these are the pretty well-known ones (great white shark, hammerhead shark, etc.) and this post is getting pretty big, so I'm happy to have presented cool unique ones already! Have a nice day, and don't forget - there are always more shark species to learn about!

#sharks #acanthodii #chondrichthyes #holocephali #chimera #ray #shark #fishblr

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sirus-themonster · 9 months ago

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Here’s some shark breads tha no one asked for but I’m doing anyway!:

African angelshark

African dwarf sawshark

African lanternshark

African ribbontail catshark

African sawtail catshark

American pocket shark

Angelshark

Angular angelshark

Angular roughshark

Antilles catshark

Arabian carpetshark

Arabian catshark

Arabian smooth-hound

Argentine angelshark

Arrowhead dogfish

Atlantic angel shark

Atlantic sawtail catshark

Atlantic sixgill shark

Atlantic sharpnose shark

Atlantic weasel shark

Australian angelshark

Australian blackspotted catshark

Australian blacktip shark

Australian grey smooth-hound

Australian marbled catshark

Australian reticulate swellshark

Australian sawtail catshark

Australian sharpnose shark

Australian spotted catshark

Australian swellshark

Australian weasel shark

Azores dogfish

Bahamas sawshark

Bali catshark

Balloon shark

Banded houndshark

Banded sand catshark

Banded wobbegong

Bartail spurdog

Barbelthroat carpetshark

Barbeled houndshark

Bareskin dogfish

Basking shark

Beige catshark

Bigeye houndshark

Bigeye sand tiger

Bigeye thresher shark

Bighead catshark

Bighead spurdog

Bignose shark

Bigeyed sixgill shark

Birdbeak dogfish

Blackbelly lanternshark

Black dogfish

Blackfin gulper shark

Blackgill catshark

Blackmouth catshark

Blackmouth lanternshark

Blacknose shark

Black roughscale catshark

Blackspot shark

Blackspotted catshark

Blackspotted smooth-hound

Blacktail reef shark

Blacktailed spurdog

Blacktip reef shark

Blacktip sawtail catshark

Blacktip shark

Blacktip tope

Black wonder catshark

Blind shark

Blotched catshark, two different species

Blotchy swellshark

Blue-eye lanternshark

Bluegrey carpetshark

Blue shark

Bluntnose sixgill shark

Blunt-nose spiny dogfish

Blurred lanternshark

Boa catshark

Bonnethead shark

Borneo broadfin shark

Borneo shark

Bramble shark

Brazilian sharpnose shark

Bristled lanternshark

Bristly catshark

Broadbanded lanternshark

Broadfin sawtail catshark

Broadfin shark

Broadgill catshark

Broadhead catshark

Broadmouth catshark

Broadnose catshark

Broadnose sevengill shark

Broad-snout lanternshark

Brownbanded bamboo shark

Brown catshark

Brown lanternshark

Brown shyshark

Brown smoothhound

Brownspotted catshark

Bull shark

Burmese bamboo shark

Campeche catshark

Caribbean lanternshark

Caribbean reef shark

Caribbean roughshark

Caribbean sharpnose shark

Caribbean smooth-hound

Carolina hammerhead

Cenderawasih epaulette shark

Chain catshark

Chilean angelshark

Chilean lanternshark

Clouded angelshark

Cloudy catshark

Coates' shark

Cobbler wobbegong

Collared carpetshark

Combtooth dogfish

Combtooth lanternshark

Common smooth-hound

Comoro catshark

Cook's swellshark

Cookiecutter shark

Copper shark

Coral catshark

Creek whaler

Crested bullhead shark

Crocodile shark

Crying catshark

Cuban dogfish

Cuban ribbontail catshark

Cylindrical lanternshark

Cyrano spurdog

Daggernose shark

Dark freckled catshark

Dark shyshark

Deepwater catshark

Deepwater sicklefin houndshark

Dense-scale lantern shark

Disparate angelshark

Draughtsboard shark

Dumb gulper shark

Dusky catshark

Dusky shark

Dusky smooth-hound

Dusky snout catshark

Dwarf catshark

Dwarf false catshark

Dwarf gulper shark

Dwarf lanternshark

Dwarf sawtail catshark

Dwarf smooth-hound

Dwarf spotted wobbegong

Eastern angelshark

Eastern banded catshark

Eastern highfin spurdog

Eastern longnose spurdog

Eastern spotted gummy shark

Edmund's spurdog

Elongate carpetshark

Epaulette shark

False catshark

False lanternshark

False smalltail shark

Fat catshark

Fatspine spurdog

Fedorov's catshark

Filetail catshark

Finetooth shark

Flaccid catshark

Flagtail swellshark

Flapnose houndshark

Flathead catshark

Floral banded wobbegong

Formosa swellshark

Freckled catshark

Frilled shark

Fringefin lanternshark

Frog shark

Galapagos bullhead shark

Galapagos shark

Galbraith's catshark

Ganges shark

Garrick's catshark

Gecko catshark

Genie's dogfish

Ghost catshark

Ginger carpetshark

Goblin shark

Graceful catshark

Graceful shark

Granular dogfish

Great hammerhead

Great lanternshark

Great white shark

Green-eye spurdog

Green lanternshark

Greenland shark

Grey bamboo shark

Grey sharpnose shark

Grey smooth-hound

Grinning catshark

Guadalupe lanternshark

Gulf catshark

Gulf of Mexico filetail catshark

Gulf smooth-hound

Gulper shark

Gummy shark

Halmahera epaulette shark

Hardnose shark

Harlequin catshark

Hasselt's bamboo shark

Hawaiian lanternshark

Hidden angelshark

Highfin dogfish

Hoary catshark

Honeycomb Izak

Hooded carpetshark

Hooktooth dogfish

Hooktooth shark

Horn shark

Human's whaler shark

Humpback catshark

Humpback smooth-hound

Iceland catshark

Indian swellshark

Indonesian angelshark

Indonesian filetail catshark

Indonesian greeneye spurdog

Indonesian houndshark

Indonesian shortsnout spurdog

Indonesian speckled carpetshark

Indonesian speckled catshark

Indonesian whaler shark

Indonesian wobbegong

Izak catshark

Izu catshark

Jaguar catshark

Japanese angelshark

Japanese bullhead shark

Japanese catshark

Japanese roughshark

Japanese sawshark

Japanese shortnose spurdog

Japanese spurdog

Japanese topeshark

Japanese velvet dogfish

Japanese wobbegong

Kermadec smooth hound

Kermadec spiny dogfish

Kitefin shark

Knifetooth dogfish

Lana's sawshark

Largenose catshark

Largespine velvet dogfish

Largetooth cookiecutter shark

Leafscale gulper shark

Lemon shark

Leopard catshark

Leopard epaulette shark

Leopard shark

Lined catshark

Lined lanternshark

Little gulper shark

Little sleeper shark

Lizard catshark

Lollipop catshark

Lombok highfin spurdog

Longfin catshark

Longfin mako

Longfin sawtail catshark

Longhead catshark

Longnose catshark

Longnose houndshark

Longnose pygmy shark

Longnose sawshark

Longnose sawtail catshark

Longnose spurdog

Longnose velvet dogfish

Longsnout dogfish

Longnose sleeper shark

Lowfin gulper shark

Magnificent catshark

Mandarin dogfish

Mangalore houndshark

McMillan's catshark

Megamouth shark

Mexican angelshark

Mexican hornshark

Milk-eye catshark

Milk shark

Mini gulper shark

Moller's lanternshark

Mosaic gulper shark

Mouse catshark

Mud catshark

Mukah river shark

Narrowbar swellshark

Narrowfin smooth-hound

Narrowhead catshark

Narrowmouthed catshark

Narrownose smooth-hound

Narrowtail catshark

Natal shyshark

Necklace carpetshark

Nervous shark

Network wobbegong

New Caledonia catshark

New Zealand catshark

New Zealand lanternshark

Night shark

Ninja lanternshark

Northern river shark

Northern sawtail catshark

Northern spiny dogfish

Northern wobbegong

Nurse shark

Nursehound

Nurseblood

Oakley's catshark

Oceanic whitetip shark

Ocellate topeshark

Ocellated angelshark

Oman bullhead shark

Onefin catshark

Orange spotted catshark

Ornate angelshark

Ornate dogfish

Ornate wobbegong

Pacific angelshark

Pacific nurse shark

Pacific sharpnose shark

Pacific sleeper shark

Pacific smalltail shark

Pacific spadenose shark

Pacific spiny dogfish

Painted swellshark

Pale catshark

Pale spotted catshark

Panama ghost catshark

Papua shorttail lanternshark

Papuan epaulette shark

Pelagic thresher shark

Peppered catshark

Phallic catshark

Philippines angelshark

Philippines ribbontail catshark

Philippines swellshark

Pigeye shark

Pink lanternshark

Pinocchio catshark

Plunket's shark

Pocket shark

Pondicherry shark

Porbeagle shark

Port Jackson shark

Portuguese dogfish

Prickly dogfish

Prickly shark

Puffadder shyshark

Pygmy lanternshark

Pygmy ribbontail catshark

Pygmy shark

Quagga catshark

Rasptooth dogfish

Redspotted catshark

Reticulated swellshark

Roughback catshark

Rough longnose dogfish

Roughskin catshark

Roughskin dogfish

Roughskin spurdog

Roughtail catshark

Rusty carpetshark

Rusty catshark

Saddle carpetshark

Saddled swellshark

Sailback houndshark

Sailfin roughshark

Salamander shark

Saldanha catshark

Salmon shark

Sandtiger shark

Sandbar shark

Sarawak pygmy swellshark

Sarawak smooth-hound

Sawback angelshark

Scalloped bonnethead

Scalloped hammerhead

Scoophead

Sculpted lanternshark

Seychelles carpetshark

Seychelles gulper shark

Seychelles spurdog

Sharpfin houndshark

Sharpnose sevengill shark

Sharptooth houndshark

Sharptooth smooth-hound

Sherwood dogfish

Shortbelly catshark

Shortfin mako

Shortfin smooth lanternshark

Shortnose demon catshark

Shortnose sawshark

Shortnose spurdog

Shortspine spurdog

Shorttail lanternshark

Shorttail nurse shark

Sicklefin houndshark

Sicklefin lemon shark

Sicklefin smooth-hound

Sicklefin weasel shark

Silky shark

Silvertip shark

Sixgill sawshark

Slender bamboo shark

Slender catshark

Slender gulper shark

Slender sawtail catshark

Slender smooth-hound

Slender weasel shark

Sliteye shark

Smallbelly catshark

Smalldorsal catshark

Smalleye catshark

Smalleye hammerhead

Smalleye lantern shark

Smalleye pygmy shark

Smalleye smooth-hound

Smallfin catshark

Smallfin gulper shark

Small-spotted catshark

Smalltail shark

Smalltooth sand tiger

Smoothback angelshark

Smooth hammerhead

Smooth lanternshark

Smoothtooth blacktip shark

Snaggletooth shark

Sombre catshark

South China catshark

Southern African frilled shark

Southern dogfish

Southern lanternshark

Southern lollipop catshark

Southern mandarin dogfish

Southern sawtail catshark

Southern sleeper shark

Spadenose shark

Sparsetooth dogfish

Spatulasnout catshark

Speartooth shark

Speckled carpetshark

Speckled catshark

Speckled smooth-hound

Speckled swellshark

Spined pygmy shark

Spinner shark

Spiny dogfish

Splendid lanternshark

Spongehead catshark

Spotless catshark

Spotless smooth-hound

Spottail shark

Spotted-belly catshark

Spotted estuary smooth-hound

Spotted houndshark

Spotted wobbegong

Springer's sawtail catshark

Starspotted smooth-hound

Starry catshark

Starry smooth-hound

Steven's swellshark

Straight-tooth weasel shark

Striped catshark

Striped smooth-hound

Sulu gollumshark

Swellshark

Taillight shark

Tailspot lanternshark

Taiwan angelshark

Taiwan saddled carpetshark

Taiwan spurdog

Tasselled wobbegong

Tawny nurse shark

Thorny lanternshark

Thresher shark

Tiger catshark

Tiger shark

Tope shark

Triton epaulette shark

Tropical sawshark

Variegated catshark

Velvet belly lanternshark

Velvet catshark

Velvet dogfish

Viper dogfish

West African catshark

West Indian lanternshark

Western angelshark

Western gulper shark

Western highfin spurdog

Western longnose spurdog

Western spotted catshark

Western spotted gummy shark

Western wobbegong

Whale shark

Whiskery shark

White-bodied catshark

Whitecheek shark

White-clasper catshark

Whitefin dogfish

White-fin smooth-hound

Whitefin swellshark

Whitefin topeshark

White ghost catshark

White-margin fin smooth-hound

Whitemarked gollumshark

Whitenose shark

Whitesaddled catshark

Whitespotted bamboo shark

Whitespotted bullhead shark

Whitespotted catshark

Whitespotted smooth-hound

Whitetail dogfish

White-tip catshark

Whitetip reef shark

Whitetip weasel shark

Winghead shark

Yellowspotted catshark

Zebra bullhead shark

Zebra shark

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spinchboli · 2 years ago

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I love you frilled sharks I love you goblin sharks I love you viper dogfish I love you Greenland sharks I love you Cookie cutter sharks I love you crocodile sharks I love you winghead sharks I love you angular roughsharks I love you whitetip reef shark I love you epaulette shark I love you deep sea dragon fish I love you barrel eye I love you viper fish I love you frog fish I love you tripod fish I love you angler fish I love you hatchet fish I love you fangstooth I love you lantern fish I love you deep sea giant isopods I love you vampire squid I love you glass squid I love you blobfish I love you chimeara I love you hagfish I love you deep sea lizard fish I love you snaggletooth eel I love you lancet fish I love you sturgeon I love you moray eel I love you worm goby I love you lemon shark I love you great white shark I love you mako shark I love you thresher shark I love you salmon shark I love you deep sea skate I love you megamouth shark I love you sixgill shark I love you sleeper shark Iove you bigfin squid I love you white spot jellyfish I love you firework jelly fish I love you telescope fish I love you gulper eel I love you snipet eel I love you oarfish I love you sea butterfly I love you firefly squid I love you ceolocanth I love you crocodile snake eel I love you crocodile fish I love you sea Angel I love you alligator gar I love you wels catfish I love you arapaima I love you piranha I love you koi fish daggernose sharks I love you threadfin snailfish I love you bony earred ass fish I love you sea robin I love you plecos I love you sawfish I love you sawshark I love you leopard shark I love you zebra shark I love you wobbegong shark I love you angel shark I love you sand tiger shark I love you deep sea batfish I love you bamboo sharks I love you rattail fish I love you nautilus I love you squid worm I love you fish creatures all very very much

#theres more butbshshd #autism posting #fish #sharks #deep sea life #i love fish so so so so much they're so fucking cool #deep sea fish gotta be one of my favorite genders #reptile appreciation coming soon

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neo-cirucs · 2 years ago

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·— SHARK NEOS —·

shark/sharks/sharkself

teeth/teeths/teethself

bite/bites/biteself

chomp/chomps/chompself

fin/fins/finself

swim/swims/swimself

gill/gills/gillself

jaw/jaws/jawself

sea/seas/seaself

ocean/oceans/oceanself

hunt/hunts/huntself

🦈/🦈s/🦈self

🌊/🌊s/🌊self

🫧/🫧s/🫧self

↓ types of sharks ↓

megalodon/megalodons/megalodonself

sawshark/sawsharks/sawsharkself

porbeagle/ porbeagles/porbeagleself

angelshark/angelsharks/angelsharkself

catshark/catsharks/catsharkself

smoothhound/smoothhounds/smoothhoundself

hammerhead/hammerheads/hammerheadself

sandtiger/sandtigers/sandtigerself

thresher/threshers/thresherself

great/white/greats/whites/greatself/whiteself

wobbegong/wobbegongs/wobbegongself

cookiecutter/cookiecutters/cookiecutterself

kitefin/kitefins/kitefinself

pygmy/pygmys/pygmyself

mako/makos/makoself

sixgill/sixgills/sixgillself

megamouth/megamouths/megamouthself

basking/baskings/baskingself

bluntnose/bluntnoses/bluntnoseself

carpetshark/carpetsharks/carpetsharkself

broadnose/broadnoses/broadnoseself

roughshark/roughsharks/roughsharkself

#pronouns #neopronoun coining #neopronouns #xenopronouns #sharks

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sharkfactoftheday · 6 years ago

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The sixgill sawshark tends to be slightly larger than other sawsharks, with males reaching lengths of 112 cm (44 in) and females reaching 136 cm (54 in).

#shark facts #sawsharks #sharks #sharkfactoftheday

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wildernessphotos · 5 years ago

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We've just discovered two new shark species – but they may already be threatened by fishing

We’ve just discovered two new shark species – but they may already be threatened by fishing

One of the newly discovered sixgilled sawshark species (Pliotrema kajae). Simon Weigmann, Author provided

Per Berggren, Newcastle University and Andrew Temple, Newcastle University

Finding a species that’s entirely new to science is always exciting, and so we were delighted to be a part of the discovery of two new sixgill sawsharks (called Pliotrema kajae and Pliotrema annae) off…

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#article #discovered #fishing #new #overfishing #Sawshark #species #threatened

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cloudtales · 5 years ago

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We've just discovered two new shark species – but they may already be threatened by fishing

We’ve just discovered two new shark species – but they may already be threatened by fishing

One of the newly discovered sixgilled sawshark species (_Pliotrema kajae_). Simon Weigmann, Author provided

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hajime-isayama-official · 8 years ago

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What kind of sharks would the 104th and vets be?

Mikasa: Great white SharkReiner: Hammerhead SharkBertholdt: Basking SharkAnnie: Nurse SharkEren: Thrasher SharkJean: Mako SharkMarco: Zebra SharkSasha: Tiger SharkConnie: Spiny dogfish SharkHistoria: Blue SharkArmin: Wobbegong sharkYmir: Bluntnose Sixgill Shark

Levi: Bahamas SawsharkHanji: Port Jackson SharkErwin: Bronze Whaler SharkNanaba: Blacktip Reef SharkMike: Whale SharkMoblit: Goblin Shark

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b33viemm · 6 months ago

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Day 30: Original Pride Flag (Gilbert Baker) Bluntnose Sixgill Shark

ID in alt Click for higher quality

I chose to pair this flag with this shark because the bluntnose sixgill shark belongs to the oldest-known shark lineages. The original pride flag -created by Gilbert Baker in 1978 and commissioned by gay activist Harvey Milk- had 8 stripes (pink, red, orange, yellow, green, turquoise, indigo, and violet) instead of 6 (pink was removed for fabric shortages, and turquoise to make an even number). Although the 6-stripe version is the most popular and mainstream, I love this version the most, and like the shark, it is the oldest of it's kind.

🩷❤️🧡💛💚🩵💙💜

THIS IS IT!!! Thank you all so much for the kind comments and support (especially on discord)! I loved doing this last year and loved it again this year, although I certainly had a lot more fun. Thank you to the goobers (you know who you are) for providing me with sharks (and for making me do this in the first place). Thanks to anyone who gave shark or flag requests! I hope you saw yourself in at least one of these ❤️

Collage of all the sharks is up! [Link]

Check my Instagram highlights (b33viemm) for all the June drawings from this year and last year. They're all also up here on Tumblr if you scroll down to June of 2023. Click this link -> #b33viemm art.

Let me know which shark is your favorite!

Click below for all the links to each drawing! [Warning: very long list]

1 - Lesbian Whale Shark

2 - Transgender Tiger Sharks

3 - Abrosexual Lemon Shark

4 - Bigender Thresher Shark

5 - Aromantic Angel Shark

6 - Pansexual Hammerhead

7 - Genderfluid Bonnethead Shark

8 - Intersex Pacific Spadenose

9 - Asexual Epaulette Shark

10 - Bisexual Nurse Shark

11 - Gay Leopard Shark

12 - Nonbinary Horn Shark

13 - Aroace Basking Shark

14 - Sapphic Zebra Sharks

15 - Unlabeled Brown Shyshark

16 - Kleegender Oceanic Whitetip

17 - Genderqueer Wobbegong

18 - Achillean Bull Shark

19 - Voidpunk Catshark

20 - Leather Greenland Shark

21 - Nebularomantic Goblin Shark

22 - Lesboy Frilled Shark

23 - Gaybian Bahamas Sawshark

24 - Uranic Giant Manta Ray

25 - Demigender Port Jackson Shark

26 - Gendervoid Chimaera "Ghost Shark"

27 - Bi Nonbinary Spiny Angelshark

28 - Queer Great White Shark

29 - Rainbow Flag Bamboo Shark

30 - That's all, folks!

Edit:

1b - Disability Pride Silky Shark!!!

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focusonthegoodnews · 5 years ago

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Scientists discover two new shark species with chainsaw-like noses

Good News Notes:

“Researchers have identified two new species of shark in the waters off eastern Africa. The rare little creatures range from about three to four-and-a-half feet in length and belong to a group called sixgill sawsharks. Their discovery came as a surprise to scientists, who previously knew of only a single species of sixgill sawshark.

‘The present study…[reinforces]…

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kristablogs · 5 years ago

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Scientists discover two new shark species with chainsaw-like noses

Sawsharks are known for their long, flat snouts studded with teeth, which they use to slash their prey to ribbons. Researchers have found two new species of this shark in the waters off eastern Africa. (Courtesy of Simon Weigmann/)

Researchers have identified two new species of shark in the waters off eastern Africa. The rare little creatures range from about three to four-and-a-half feet in length and belong to a group called sixgill sawsharks. Their discovery came as a surprise to scientists, who previously knew of only a single species of sixgill sawshark.

“The present study…[reinforces] both how important the western Indian Ocean is in terms of shark and ray biodiversity, but also how much we still have left to find,” Simon Weigmann, a marine biologist at the Elasmobranch Research Laboratory in Hamburg, told Popular Science in an email. He and his colleagues reported their findings on the new sharks on March 18 in the journal PLoS ONE.

Sawsharks are known for their long, flat snouts studded with teeth, which they use to slash their prey to ribbons. They’ve saw The sea animals have similar chainsaw-like mouths to another ocean fish, known as the sawfish, though they aren’t at all related. Sawfish are actually rays and can grow up to 23 feet long.

The newly recognized sawsharks, like their cousins, have whisker-like organs called barbels that they use to detect food. (Courtesy of Simon Weigmann/)

Most sawsharks have five gill slits on each side of their bodies, as is typical for sharks. Until now, the only sawshark species thought to have six gill slits—known as Pliotrema warreni—was found in the waters around South Africa and southern Mozambique.

This unusual feature doesn’t seem to play a vital role in the sharks’ survival. “The presence of six (or seven) gill slits per side is considered a characteristic of very primitive sharks,” Weigmann said. “There is no advantage known for them in having six gill slits.”

The first hint that P. warreni wasn’t the only six-gilled sawshark in the sea came in 2017, when a fisherman in the village of Andavadoaka in southwest Madagascar contacted Weigmann’s colleague Ruth Leeney, who is based at the Natural History Museum in London. At the time, she was studying sawfish in Madagascar. The fisherman told her that he’d just caught two of the rays. But the animals turned out to belong to an entirely new species of six-gilled sawshark rather than a new variety of ray. Weigmann and his team were able to identify several more members of this previously overlooked species in museum collections.

Then in 2017 and 2019, a few more of Weigmann’s colleagues mailed him two sawsharks that fishermen had captured as by-catch off the coast of Zanzibar. After a thorough examination, the researchers declared the specimens to be a third species of sixgill sawshark.

The newly recognized sharks were named Kaja’s sixgill sawshark and Anna’s sixgill sawshark in honor of Weigmann’s daughter and niece. Their snouts are shaped slightly differently from that of their cousin P. warreni. All three sharks have whisker-like organs called barbels that they use to detect food; they’re also found on catfish. However, the newly discovered sharks’ whiskers are placed farther from the mouth. It appears that none of the sixgill sawshark species have overlapping ranges.

“The identification and formal description of the two new species is extremely important for evaluating their rarity and population status, as well as for assessing their vulnerability to fishing operations,” Weigmann said. He is particularly concerned about Anna’s sixgill sawshark, which has, as of yet, only been seen in shallow waters, a location where it might easily end up in a fisherman’s catch by accident.

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scootoaster · 5 years ago

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Scientists discover two new shark species with chainsaw-like noses

The newly recognized sawsharks, like their cousins, have whisker-like organs called barbels that they use to detect food. (Courtesy of Simon Weigmann/)

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