#Valvatida

[snototter]

A red cushion sea star (Oreaster reticulatus) in Rendezvous Bay, Saint John, Virgin Islands

by Alan Cressler

[uncharismatic-fauna]

Uncharismatic Fact of the Day

Most animals need blood to survive, but not starfish! None of the over 2,000 species of sea star have blood, although they do have a circulatory system. To transport oxygen and nutrients through their body, starfish pump seawater through an opening called the madreporite into their bodies. Starfish also use this system to move by contracting various muscles and forcing water into or out of their limbs.

(Image: A cluster of ochre sea stars (Pisaster ochraceus) by David Job)

If you like what I do, consider buying me a ko-fi!

[rattyexplores]

The Indo-Pacific Sand Star

Not as colorful as you’d imagine a sea star to be. Yet, still lovely creatures.(These stars traverse the sands on the sea shores, watch where you step!)

There also appear to be small snails on the underside of Specimen 1.

Archaster typicus

15/06/22

[magnapinna-nightmare]

Ocean Animal of the Week.

Today is an important day.

Today marks the birth anniversary of a fictional man who is very dear to my abyssal heart. I will not explain who it is. You will all simply have to find out for yourselves.

One of the creatures I find myself associating with him is the Crown of Thorns Starfish.

What majestic creatures!

Crown of Thorns Starfish (or Sea Stars) are born of the order Valvatida, and the family Acanthasteridae.

They were given their names based on the venomous spines that coat their bodies. Their spines are very toxic to humans and other animals, but not all are weak to its poison. Creatures such as the giant Triton snail, Humphead Maori Wrasse, and Titan Triggerfish are a few of this creature's natural predators.

This starfish's diet consists primarily of coral, and they can have devastating effects on coral reef ecosystems.

These creatures can release millions of eggs. Many sea stars are known for having extremely large clutches.

This is a starfish in its bipinnial larva stage. Look how adorable their baby photos are. Don't you just want to pinch its cheeks?

Some starfish reproduce through both sexual reproduction and asexual reproduction, their asexuality being shown through binary fission and regeneration. These dual reproduction methods classifies those starfish as bisexual. Good for them.

Strangely, unlike those other starfish, these specific sea stars are not known to reproduce asexually, and instead often reproduce by releasing their gametes into the open water and waiting for them to be fertilized.

Other facts:

-If you so happen to be "stung" by this starfish, the symptoms may include redness and swelling. In more severe reactions, there may be tingling, numbness, weakness, nausea and/or vomiting, joint aches and headaches, and in more serious and rare cases, paralysis.

-They can kill off entire coral colonies from how voracious they can be.

-There is a pokemon based on them! Mareanie and Toxapex are reportedly based on these starfish, and you can clearly see the resemblance in their spines.

-They prefer to eat branching corals and table-like corals. They have good taste.

-If hard corals are scarce, they may potentially feed on soft corals.

-They can have around 21 arms!

-They are one of the biggest starfish species in the world, but are still smaller than starfish such as the Sunflower Starfish. The Sunflower Starfish is reportedly 1 m/3.3 feet, while the Crown of Thorns Starfish reaches 45 cm.

-Sea stars and Starfish are technically the same thing, just beneath a different name. Some call these creatures "Sea Stars" instead of "Starfish", considering they don't classify beneath the term of "fish".

-They are very cute. :]

These creatures may be harmful to coral reefs, and that is a large concern.. But they are still a majestic species! Their beauty is indescribable, and they will always hold a special place in my heart!

Happy birthday to.. The man who i will not explicitly name.

[thegrandimago]

Taken the same day as the previous post, this is a common sunstar (Crossaster papposus), or solstjärna, caught in the fjord and is feasting on an unfortunate tall sea pen. In Sweden, they occur on the west coast on hard, sandy or gravelly bottoms within 10-50 m depths. For sessile and slow-moving invertebrates, these 35mm in diameter beasties are vicious predators that travel 35-50 cm a minute and will even devour other sea star. Before they become the predator shown here, they start out life during the late spring as free-swimming larvae for a short period that feed on nothing as they swim in groups before settling to the bottom. #animal #animals #djur #wildlife #natur #naturliv #nature #fauna #invertebrate #invertebrates #seastar #seastars #sjöstjärnor #sjöstjärna #asteroid #asteroids #sunstar #sunstars #echinoderm #echinoderms #tagghudingar #animalia #echinodermata #asteroidea #valvatida #solasteridae #crossaster #crossasterpapposus #commonsunstar #solstjärna (at Klubbans biologiska station) https://www.instagram.com/p/CeG-NS8K06Q/?igshid=NGJjMDIxMWI=

[animalids]

Crown-of-thorns starfish (Acanthaster planci)

Photo by Kary Mar

[nature-and-biodiversity-blog]

Chocolate Chip Sea Star Protoreaster nodosus

[alphynix]

Almost-Living Fossils Month #03 -- The Crowned Starfish

Known mainly from around Europe -- with a few records from the Atlantic coast of North America and the Caribbean -- the stauranderasterids were a family of starfish that first appeared about 190 million years ago in the Early Jurassic.

Not much is known about their life ecology, although they seem to have inhabited shallow tropical seas and like many other starfish would probably have preyed on various slow-moving marine invertebrates. Complete specimens are very rare compared to just isolated elements, making their maximum size difficult to estimate, but they likely grew to at least 5-10cm across (2″-4″).

They had enlarged ossicles forming a bumpy “crown” over their central disc, with five arms that could be either narrow and elongated (such as in Stauranderaster coronatus here) or shorter and club-shaped (like Manfredaster bulbiferus). This gave them some visual similarities to modern starfish like Protoreaster, and since they were both part of a larger grouping of starfish called valvatids it’s unclear whether these features mean that they were very closely related to each other or if it was simply due to convergent evolution.

The stauranderasterids survived until at least the Late Paleocene/Early Eocene (~56 mya), but some possible remains from Cuba date to as recently as the Early Micoene (~23-16 mya).

[professionalunprofessional]

I think this is the Red Cushion Starfish, which is also known as the West Indian Sea Star! Did you know that starfish aren’t fish, but Echinoderms? Despite this I will also be adding the ’Fish’ tag, just to make it easier for y’all!

[trans-mando]

I love fieldwork. Look at the duckies.

(we did not feed or encourage them)

(sound on for duckie noises)

Other wildlife at this site: some valvatidae snails, a couple of simuliidae larvae, and some lil bitty hirudinea

[snototter]

A chocolate chip sea star (Protoreaster nodosus) in Sulawesi, Indonesia

by Bernard Dupont

[encyclopika]

Animal Crossing Fish - Explained #120

Brought to you by a marine biologist who can’t wait to tell you about sea stars...

CLICK HERE FOR THE AC FISH EXPLAINED MASTERPOST!

How magical is our world that there’s a majestic sea creature shaped like a star? Honestly, we take this place for granted. And what’s more, this beautiful, magical thing is also a little bit of a monster. Ain’t that something? :)

Sea Stars (NOT starfish...this ain’t a fish, keep up) are Echinoderms. Echinoderm literally means “spiny skin” and that’s precisely what many of them are like, particularly Sea Urchins. Sea Stars are a bit more flexible, having anywhere from 5 to 40 arms, depending on the species. Sea Stars make up Class Asteroidea, for which there are 1500 species and probably many more, as sea stars can be found literally everywhere there is salt water, from coastal estuaries to the abyssal plain. 

The species represented in Animal Crossing appears to have changed since we were diving in New Leaf, and it is now the fatter Anthaster valvulatus, the Brick Red Sea Star, a coastal species of the South Pacific. It is a species within Order Valvatida, which have prominent ossicles, or calcerous elements that are embedded in the skin. Looked to me the ACNH model had some obvious bumps, so I chose this species, but I’m not as sure as I usually am. Nevertheless, the species is often recorded close to shore in Australia, and ACNH put it in the Coastal Tank, so I’m not exactly guessing here.  

By Peter Southwood - Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=31748978

Sea Stars are so insanely cool, that I wish they’d given us two Sea Stars rather than two kinds of Sea Urchins so I could really cover it all. When I used to teach at my local aquarium, I used to tell people I had 3 very important things to tell them about the Sea Star, and this goes into my statement about these things being magical little monsters.

1: Sea Stars have eyes. Like when we went over the Scallop, Sea Stars have simple eyes, one stationed at the tip of each arm, that allow them to see gradients of light and dark and some movement. This allows them to figure out where to go next or if they need to hide.

2: Sea Stars have incredible regenerative powers like their cousins the Sea Cucumbers. If you cut a Sea Star perfectly in half, you’ll get yourself two new Sea Stars. As long as the central disc of the animal is attached, it will grow completely back. It’s slow, but this ability allows them to come back from predator attacks and disease with a vengeance. 

3: And lastly, Sea Stars are voracious predators that eat bivalves. Unlike the Whelk we just covered yesterday, the Sea Star doesn’t have any hard parts to hammer against its preys’ shells. So how does a Sea Star eat the meat inside a clam shell? Well, they pry it open with their bare arms, of course! Sea Stars have a water vascular system that allows them to move on their tube feet, but it also allows them to steadily pull their prey’s shell open without getting tired. They’ll pull and pull for *days*, wearing out the bivalve until they, working on muscle power, tire out. 

So, okay, they got the shell open, now how are they eating anything? The Sea Star’s mouth is underneath it at the center of its body. Once it has the shell open, it extends its stomach out of its body and into the shell where it dissolves its prey in digestive enzymes outside its body. Then it slurps it all up and leaves a perfectly opened shell. 

Echinoderms are nuts and Sea Stars are the kings.

And there you have it. Fascinating stuff, no?

[every1studio]

REQUESTED: “a mermaid’s cupid” [ateez]

genre: FLUFF + slight angst? + fiction/fantasy 

ficstyle: bulletpoint + reactions 

requested: “ mermaid!Ateez reaction to falling in love with a human???? “

note: I still feel so uninspired to write but I hope this is something for this week 

HONGJOONG 

you let your tears drop into the ocean as you sat on the shoreline  

the sand and ocean waves made your wedding dress all dirty and tattered

the mild, salty wind undid your bridal updo 

you were a mess; physically and emotionally 

you were left at the alter; realizing that your soon-to-be husband ran off with your best friend 

you wanted to turn into seafoam in that moment 

Hongjoong watched you on his daily swim to the shore 

how could anyone ever make someone as beautiful as you cry?

he read about humans all the time and judging by your attire, it was suppose to be your wedding day 

so why weren’t with the person that was suppose to make you happy for the rest of your life?

Hongjoong wanted nothing than for you to smile; it hurt him to see you in so much pain 

he took off his prized pearl necklace and swam as close as he could in your direction 

it was from his first love; she was a human who was years older than he was but that didn’t stop him from loving her. when she told him that she had to follow through with an arranged marriage. so she gave him her necklace so that he wouldn’t forget her.. 

seeing you in a wedding dress made him remind you of her  

you didn’t even notice him at first

you thought it was just the waves 

but when you saw a pair of hands, you fell back; startled at the sight of the mystical creature 

he places the pearl necklace on your lap and brings his hands up to wipe your tears away

“whatever or whoever it was, they aren’t worthy of your tears...” he says before slipping back into the sea for a breath 

you stood up to see where he went but he disappeared into the deep, blue waters 

you held onto the necklace knowing that this wasn’t a dream 

you hoped for the next day, you’ll be able to see him again 

little did you know, he hoped for the same 

and as if the stars in the skies were aligned, Hongjoong emerged from the surface only to have you greet him with his necklace around your neck

he knew you weren’t her; but these feelings he had inside weren’t for her but for you  

SEONGHWA

it was a stormy day at the beach 

but that didn’t stop you for trying to get the perfect pictures of the storm 

you stood near the cliff 

not worried about any dangerous aspects of getting the shot 

the moment you got the shot, you lost footing 

you dropped your camera on the cliff and you were falling into the ocean

the force of hitting against the surface of the ocean caused you to become unconscious

Seonghwa saw everything that had happen and swam to rescue you 

you sunk too far into the ocean

even if he swam as fast as he could up to shore, there was a possibility that you would’ve drowned 

he locked lips with you; transferring as much air as he could, which would’ve been more than enough until he got to the surface

the storm had settled down by the time that he got you onto shore 

“come on, come on..” he mutters as he performs CPR on you; he learned this as from the TV shows he would occasionally watched 

you sputtered out water as he breathes in relief

he didn’t even how beautiful you were as he was hovering over you

and when you fluttered your eyes open, he didn’t know what to do 

he was completely flustered as he backed up to give you some space

that was also when he forgot he couldn’t be seen by humans; he was considered to be a rare species after all 

but when he saw how calm you were, he was too

“you’re beautiful..” you managed to say as you rubbed your chest 

“and so are you- are..are you not scared? or surprised?” Seonghwa asks as he points at his tail 

“I always knew there was something magical about this coast... I was saved just like this when I was a little kid.. so I knew your kind existed..”

his eyes widened as his memories started to rush from being locked away for so long, “Y/N?”

your heart lurched out of your chest, “Seonghwa?”

YUNHO 

you had just moved closer to the beach after wanting to start a new life

you went exploring around until you found a cove; it had a danger sign in front of it

you ignored it as you were feeling a little adventurous 

it seemed like it wasn’t the usual tourist area; more like a place the locals wanted to keep for themselves

it was quite hidden from the city; it was a beautiful place, it was covered yet there was rays of light to light up the whole cove 

as you were taking in all the beauty of the cove

Yunho was taking in all the beauty of you

he heard footsteps inside of the cove; Yunho always scared off anyone who tried to invade his private hideaway from the stress of being a prince of the sea 

but when he saw you, he couldn’t do anything but stare

you were more beautiful than anything he’s ever seen 

the sound of water movement startled you, causing you to trip on your own foot

“I’m sorry, I didn’t mean to scare you..” he swam closer to you but kept his distance in case that he frightened you 

“I-just.. you’re a mermaid... I mean merman?” you began to stutter out of surprise, “I’ve only read about merpeople in fantasy books..”

“yeah.. well we’re real... humans can get a little obsessive about rare species like us..” he mumbles, you sensed the irritation in his voice as his hands grazed over his old scars

you slowly walked up to him and squatted down to talk to the beautifully handsome creature face to face, “I’m not like most humans..”

Yunho looked up at you with glassy eyes

you took out your hand for him to take, “I’m Y/N”

he was hesitant to take it at first, but you were patient with him

“I’m Yunho,” his cold hand welcomed your warm touch, “could you tell me more about you and humans?”

you smiled back at him, which made his chest all bubbly, “if only you tell me more you and merpeople”   

YEOSANG

Yeosang had just got caught in a fisherman’s net that was being brought up to to the boat

he knew that he was captured by a human that would be the end of his life

he struggled and struggled and his tail got scraped by the fisherman’s hook; causing his scales to drift into the ocean currents

you were surfing when you saw the struggle

you swam under the boat and pulled out your little pocket knife you in your swimmer’s bag and tried to cut the net free

Yeosang swam in the opposite direction that you were cutting so that the net would rip easier 

you were on your last couple seconds of air when you cut just enough of the net for Yeosang to escape

at first he swam away because you were a human

but when he saw you sinking down, your eyes were trying to flutter open in a struggle to try to swim up

Yeosang swam as fast as he could to save you

he was stunned for a moment to notice how beautiful you were but he had no time to just stop and gawk at you 

thankfully due to his speed, he got you up to the surface while keeping hidden from the fishermen 

you gasped for air and you were too weak to keep yourself afloat 

he brushed your hair out of your face, “are you okay?”

you looked down at his tail, “are you?”

he nods as he carried you to shore 

right after he placed you onto the sandy banks, he gave you a large piece of his scale, “thank you for saving my life..”

you rummaged in your bag for some ointment to put over his scratches, “thank you for saving mine..”

you both chuckled at the situation 

“humans are trash..” you muttered, “you are such beautiful creatures that should be left alone...”

“I don’t think you’re trash. I think you’re beautiful”

the moment you turned to look at him, he blushed intensively 

“well, see you around~” you walked over to your surfboard

“how will we know when to meet?” 

you showed him your board, “I see you every time I hit the waves.. I hope that whenever you see my board, you’ll know I’m around~”

SAN

it was early morning when you were collecting data on starfishes 

you were a marine biologist studying about common sea creatures from different area 

you reached out for a fairly large valvatida starfish when you saw another hand grab it before you could 

“hey!” you pushed up your glasses in slight annoyance until you saw who the hand belonged to

San was completely entranced by you

and you were mesmerized by him 

“c-can I study you?” you brought out your notebook 

“wh-what?” he suddenly felt the need to cover himself 

“I’m a marine biologist.. and obviously you’re a marine creature... but..” you looked up at him with a feeling that you were making him uncomfortable 

seeing you so upset made him just as upset, “you can, it’s just.. I’ve never been studied before.. what do I need to do?” 

San smiled when he saw your eyes light up, “just sit there for a second!”

you started to sketch away; San was just awkwardly sitting there with the starfish still in his hands

every time you looked up at him, he would divert his attention away from your attractive eyes; it made him nervous 

when you were done, you showed him your work; it was such an accurate sketch of himself 

“it looks like a better version of me...”

you shook your head rapidly, “nothing can ever come close to the real deal..” 

he blushed, “I need to go but I would like to come back and have you study me again?”

you giggled at his request, “same time?”

he nods, “same time.. like a date..”

MINGI

you were collecting seashells like how you you used to; moments like these make you miss your ex boyfriend 

you just sat in the sand as you were counting the amount of shells you collected

you felt someone place a beautiful conch shell into your hands

“thank-” the moment you saw the red-haired boy.. or merman, “you...”

he just smiled at you, “you looked sad while picking shells... so I found the prettiest one for the prettiest being I’ve ever seen..”

you beamed as you grazed over the shell he had just given you but all you could muster was another quiet, “thank you”

he sat there in the water as you were playing with the wet sand 

“that person didn’t make you happy?” he was referring to your ex 

you didn’t have to say anything and it was just he knew what you were thinking about 

“they did.. but I couldn’t make them just as happy..” you smiled but you were just trying to hold back tears 

“do you like the ocean?” the boy asked 

you nodded; confused with where the conversation was going 

the merman held the conch against your ear, “you can hear the ocean. I hope you can be happy every time you have this shell with you..” 

you smiled at his kind gesture; you almost forgot that you were talking with a merman, a mystical creature 

“I’m Mingi..” he tucked your hair behind your ear to get a better look at your face

you couldn’t look at him in the eyes, “I’m Y/N...”

“I wish I can make you happy..” these thoughts waved through Mingi’s head as he swam back into the ocean 

he would do anything, ANYTHING, to be the one to make you happy 

WOOYOUNG

you noticed seafoam bubbles that gathered by your feet on the beach 

it reminded you of the story of the Little Mermaid; the lighthearted yet tragic story 

as magical as it sounded, being in love with a mermaid would be such a sad love story

and you weren’t one to sign up for a sad love story 

nearby, Wooyoung was sunbathing as he noticed you playing with seafoam bubbles 

his folks always said things about falling in love with humans, saying that in the end, you’ll just become seafoam 

Wooyoung was always bound to the rules his family laid out for him 

but at the first sight of you, he couldn’t help but fall for you 

he could see his destiny ending in seafoam bubbles

but he felt like he could finally do what he wanted to do and love who he wanted to love 

the minute he saw an unknown man put his jacket around you, he wanted to make the story of the Little Mermaid his

he couldn’t stand watching someone else be by your side

he would sacrifice his tail for legs

he would sacrifice his life for love

he would sacrifice himself to be seafoam bubbles for you 

JONGHO

it was a foggy morning; that was the only time Jongho went up above the surface 

he liked how his voice sounded as it echoed against the cliffs 

little did he know, you always sat on top of the cliff after your morning run to listen to this mystery man sing 

while listening to him sing, you dropped your earphones off of the cliff

“dammit...” you mumbled as you got up to try to get him 

when you got down there, you were met with some guy holding your earphones

“oh thanks for getting those for-”

you didn’t finish your sentence, you couldn’t 

there was a beautifully built merman singing right in front of you

Jongho knew that at the sight of any human, he had to swim away

but he felt safe with you; your beauty had some sort of tranquility 

“what are these?” 

you fumbled around for your phone, “can I?” 

you reached for your earphones, Jongho felt the warmth of your hand as you took the item from him 

you gently placed an earphone in one of his ear and the other onto your, you turned on some music and Jongho was hooked

you both just sat there for hours, talking about music above the surface and technology until the fog cleared out 

when the fog cleared out was when everyone would go out to the beach, he had to leave 

“can you come back tomorrow? I would love to know more about music from phones and all of that..”

you smiled back at him, knowing that you can see him tomorrow, “only if I can hear you sing..”

“that’s a promise then”

[ masterlist + guidelines ]

[crittercatalogue]

Cnidaria Anthozoa Actiniidae Anthopleura & Echinodermata Echinoida Strongylocentrotus purpuratus & Echinodermata Asteroidea Valvatida Patritia P. miniata.

These photos are extremely exciting to me, as we get the opportunity to observe three different species sharing one large space together. All of these animals were located at the Academy of Science in San Francisco and are abundant along the central California coast and as seen here, have themselves anchored to the substrate provided by the museum, imitating what would be the intertidal zone. On observation, they did not display much movement or activity.

[animalids]

Cake sea star (Anthenea aspera)

Photo by Loh Kok Sheng

[sciencerulesblog]

Week 29: Crown of Thorns Starfish

This is the Acanthaster planci, more commonly known as the crown-of-thorns starfish. They are a part of the Animalia kingdom, the Echinodermata phylum, the Asteroidea class, the Valvatida order, the Acanthasteridae family, and the Acanthaster genus. The crown of thorns starfish are known for their vibrant colors and unique exterior. 

The crown of thorns starfish resides in the Indo-Pacific area on coral reefs. They feed on corals that help the environment of the Great Reef. They usually spwan during the warmer months, producing very large amounts of eggs. They are more likely to be attacked in their older years. 

The crown of thorns starfish come in a variety of colors, as you can see from the pictures included. The long spines that you see are venomous and they can grow up to 80 cm. For this reason, they do not have many predators, although they are still threatened by environmental factors and some predators. 

Crown of thorn starfish can appear in very high densities throughout coral reefs that are called outbreaks. They help in species diversity within reefs. 

Info sources: x x x 

Image sources: x x x