Horseshoe crabs deserve RIGHTS
yeah you're like "hahah wat"
you're like "wait what's so special about them tho-"
BRO?? MY DUDES!!! HORSESHOE CRABS ARE I M P O R T A N T. HORSESHOE CRABS CAN SAVE! YOUR!! LIFE!!! also their eggs are apparently delicious? idk i've never tried em
Let us not judge the Horseshoe Crab just because it looks like a turtle shell...rock-helmet-thing with a pointy stick attached to one end. Horseshoe crabs are valid!
So, yeah. We're gonna learn about horseshoe crabs B)
But FIRST!
We're gonna learn about beaches. >B) (:<
Snazzy Stuff!
- Fringes of land (made from loose particles) that border a body of water!
- High energy habitats that are constantly changing! Many factors that cause change
- Part that is being changed is known as the berm.
- The berm has parts to it too (':
- Part that is being changed is known as the berm.
- Look pretty empty when there aren't hordes of people (and seagulls) milling around on them!
- Very popular locations for People
- People are problematic.
What Lives Here?
Beaches may look like they're just giant expanses of sand, but if you look down, you'll see that there are some plants! Plants are beneficial to the ecosystem; they stabilize the soil to prevent erosion, provide shelter and food for other organisms, and are just really cool in general!
Bayberry, or Myrica: A genus of deciduous shrubs; their scientific name is derived from the Greek word for "fragrance." Another common name is "wax-myrtle," because the fruits of the bayberry plant have a waxy coating.
Beach Grass, or Ammophila: Moves! It rolls up to conserve it's water supply, and then unrolls when it receives water again.
Beach Pea, or Lathyrus: A genus of flowering plants that are also known as "pea vines" or "vetchlings." The beach pea species of Lathyrus japonicus naturally ranges from Europe to Asia to the Americas.
Cocklebur, or Xanthium: Also a genus of flowering plants! Cockleburs are in the daisy family and the sunflower tribe, but unlike daisies and sunflowers, they're spiny and poisonous and considered a problem on a global scale.
Dusty Miller, or Artemisia stelleriana: Grows well in arid climates! Often cultivated as an ornamental for it's silvery foliage.
Salt-spray Rose, or Rosa rugosa: A rose that is native to East Asia but has since made itself at home here. The name of "rugosa" means wrinkled; a reference to the wrinkled appearance of it's leaves.
Seaside Goldenrod, or Solidago sempervirens: A very salt-tolerant seashore species, this goldenrod can grow in salt marshes, sand dunes, and estuary banks.
What ELSE Lives Here?
I wonder what else lives on sandy beaches? It couldn't possibly be horseshoe crabs, right? RIGHT?
Horseshoe crabs live in the water, but they are hatched on beaches and return to them for mating.
There are also birds, like seagulls smh
The Taxonomy of the Horseshoe Crab
Horseshoe crabs...horseshoe crabs are not actually crabs. They're more closely related to spiders than they are crabs.
They are marine arthropods that make up the family of Limulidae and the order of Xiphosurida. Four species of horseshoe crab exist today: Carcinoscorpius rotundicauda the Mangrove Horseshoe Crab, Tachypleus gigas the Southern Horseshoe Crab, Tachypleus tridentatus the Tri-spine Horseshoe Crab, and Limulus polyphemus.
Limulus polyphemus holds the common names of the "Atlantic Horseshoe Crab" and the "American Horseshoe Crab." It is the only species of horseshoe crab in the western hemisphere; all other species occur in the waters of Asia, in the eastern hemisphere.
The subphylum of Chelicerata shows how closely related the horseshoe crab is to the spider. Arachnids like spiders and scorpions belong in Chelicerata, but true crabs do not! The similarities between horseshoe crabs and arachnids has led to debate in the scientific community as to whether or not the former should be put in the class of the latter.
| To the left is an Atlantic Horseshoe Crab | |
|---|---|
| Kingdom | Animalia |
| Phylum | Arthropoda |
| Subphylum | Chelicerata |
| Order | Xiphosura |
| Family | Limulidae |
| Genus | Limulus |
| Species | L. polyphemus |
| Code Base | Himmalerin |
There is additional debate over the horseshoe crab's class of Merostomata, which means mouth in stomach. Horseshoe crabs used to belong to this class, (there were two orders in it and the other one was extinct), but some claim that is is outdated and unnecessary. However, it continues to see use by a variety of organizations.
The Anatomy and Physiology of the Horseshoe Crab
Horseshoe crabs are actually very biologically-complex creatures! In spite of this, their bodies are categorized into three basic parts.
The Prosoma/Cephalothorax/Head is where most of the horseshoe crab's vitals are stored. So it's not just their brain located in this area, but also their heart! Some of their intestinal track! And nervous system! And circulatory system!
Underneath the prosoma are six pairs of teeny little appendages. The first pair is the most smol™. They are the chelicerae; pincers that pick up food and pass it along to the horseshoe crab's waiting mouth.
Which is in the prosoma! Smack-dab in the middle of all those teeny little legs! *Puts six pairs of legs around my mouth*
Oh, and did I mention that horseshoe crabs don't have jaws? They rip up their food on their gnathobases first before putting it in their mouths.
After the chelicerae are the pedipalps, which are legs used for walking! After those are four pairs of legs called "pusher legs," which not only help with moving, but with burrowing into the seafloor!
The Opisthosoma/Abdomen is where the gills of the horseshoe crab are located. Horseshoe crabs have five pairs of book gills, structures with more than 100 lamellae inside of them. The lamellae look like the pages of a book, hence the appendage's name.
The Telson/Caudal Spine/Tail is the stick-stinger-looking-thing at the back of the horseshoe crab. These are not actual stingers. (Or sticks) Horseshoe crabs CANNOT sting you! Horseshoe crabs are completely harmless to people! exceptformaybethatonespeciesthatstoxicifconsumed justdonteatthemangrovehorseshoecrabguys
But if the telson isn't some sort of defense mechanism, you might be wondering what it's purpose actually is. AND I SHALL TELL YOU IT!!
The Life Cycle of the Horseshoe Crab
- Hatches on the shoreline near sandy beaches! Along with 15,000 to 64,000 siblings!
- Not all of them make it
- Little horseshoe crab larva swims 'round and 'round for about a week before it gets it's first molt! The older they get the more they molt the further the swim out into the ocean.
- By the time they've matured, a horseshoe crab would have shed 16-17 times!
- A horseshoe crab is mature at around 10 years old. Their lifespan is uncertain, but they might be able to make it to 40 years.
- Once it reaches maturity, a crab will journey to a sandy beach
- Sorry, I meant crabs, not crab. Hundred of crabs will journey to a sandy beach or a similar location once they've matured.
- Females arrive with the high tide! At night with a full moon, preferably.
- They make babies
- The cycle repeats!
:sparkles: S U S T E N A N C E :sparkles:
Powers and Abilities and Random Facts
The name of their order, Xiphosura, means sword tail in Greek.
The word Limulus means skewed, and polyphemus refers to the cyclops of Greek mythology. It was once believed that Horseshoe crabs had only one eye.
Horseshoe crabs can swim upside down!
Horseshoe crabs have nine eyes! (Ten if you count that photoreceptor array that they've got on their telson)
Female horseshoe crabs are about 1/3 larger than male horseshoe crabs!
Many marine organisms attach themselves to the carapace of the horseshoe crab.
Horseshoe crabs can regrow their limbs!
The heart of a horseshoe crab only beats about 32 times per minute!
The blood of horseshoe crabs is greyish-whitish-yellow, but it turns blue when oxidized! Their blood is also important to us!
Horseshoe crab blood contains amebocytes, which coagulate around harmful bodies that are detected within the system.
All intravenous drugs made in our country must be tested with Limulus Amebocyte Lysate before they are released.
Horseshoe crabs are old! They are sometimes referred to as living fossils because of how little they have changed, even after 450 million years of existence, which means that the humble Horseshoe Crab preceded the dinosaurs by 200 million years. (Although, our genus Limulus is only about 148 million years old, not 450 million)
And unlike the dinos, horseshoe crabs are still alive. which obviously means that they are superior
Threats...
Red knots! Loggerheads!!
More Threats...
Humans!!!
My GOD Do We Have Threats!
H U M A N S S S
Solutions?
Stop being a human. Problem solved
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jk (':
Okay, some conservation efforts are being taken to protect the horseshoe crab!
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