Tag Archives: Arthropod

The California Spiny Lobster

The California spiny lobster is a unique invertebrate (species lacking a backbone) that is found off the coast of southern California. This type of lobster belongs to a group of invertebrates known as Arthropoda. Arthropoda’s characteristics consist of having a segmented body, exoskeleton, and jointed appendages. These lobsters share the same grouping classification as insects and spiders! How cool is that!

California Spiny Lobster

A California spiny lobster hiding in its den.

The California spiny lobster lacks claws, unlike its friend, the American lobster, which can be found off the eastern coast. They are also reddish-brown in color and have an enlarged pair of antennae, used for sensing their environment. These antennae can also produce a loud clicking noise to warn off predators. California spiny lobster get their name from the forward-pointing spines that cover their bodies to help protect them from predators.

California Spiny Lobster tim

Credit: Tim S

Their hard shell, or exoskeleton, also helps to protect them from predators, but can make growing a challenge. To grow, the lobster must shed their shell to increase their size! This process is called molting. To do this the lobster must reduce the size of their body in the shell, by drawing in as much water as they can, so their shell isn’t too tight. Then, the shell breaks between the tail and their body (otherwise known as a carapace). The lobster will then flex their body back and forth and eventually back out of their old shell. During this period, the lobster is shell-less, and EXTREMELY vulnerable. They must stay hidden because it’s super hard to protect themselves from prey without their hard exoskeleton protecting them. The lobster will then start the process of growing a new shell, which can take several months.

California Spiny Lobster 2

CIMI snorkelers discover a discarded lobster molt in the water!

When it comes to movement in the water, these guys are experts! With ten legs, these lobsters can walk along the sea floor, as well as move backwards and even sideways! However, if they need to move fast from predators, they can tuck their tails under their abdomens and rapidly propel themselves backwards, similar to how octopus and squid move!

These animals are nocturnal, and spend most of their day hiding in rocky crevices. At night, they leave their dens in search of a meal. Their diet ranges from algae and dead organisms to snails, sea urchins, and clams. They have even been known for cannibalism in desperate times, and have been seen feasting on injured or recently molted lobsters!

Whether you see lobsters as an interesting sea creature or a delectable meal, next time you’re at your local supermarket or on a snorkel, be sure to check out everything these amazing creatures have to offer!

California Spiny Lobster hair

Lobsters make great head masseuses and hair stylists, when they’re not busy using their ten legs for scuttling about. Credit: Gabrielle R and Capri L

P.S. For some inspiration from a rabbi on growing through adversity and learning from lobster, click here: http://www.stillworks.org/blog/2016/2/27/how-to-grow-through-stress-lessons-from-a-lobster-by-a-rabbi

Written By: Brooke Fox







The Mantis from Atlantis

Hi there! It’s me, your local friendly Mantis Shrimp, also known as the Stomatopod. I’m guest blogging for CIMI this week to set a few things straight. First of all, I’m not actually particularly friendly. I have a mean reputation for dismembering my prey – namely any octopus, snail, fish, or human thumb that comes my way – with a powerful one-two punch from my giant club claw or a hairy spear appendage, followed by a shockwave of boiling water that’ll stun you even if I miss. But I digress. My 450 family members live all over the Pacific and Indian oceans, in shallow, tropical waters. But we’re a little obscure, since, you know, living in the shadows of deep hidden rock crevices you’ll never dare to investigate, so I figured it’s time you humans saw the world through my eyes.

Speaking of eyes, I have the most developed visual system yet discovered in the animal kingdom. In your eyes, you’ve got two different types of cells that help you see: rods and cones. Rods are located around the edges of your retina, and help you see contrast, brightness, black and white, and movement. Cones, on the other hand, help you see color.

You measly humans have three types of cone cells in your retina: red-sensitive cone cells, green-sensitive, and blue-sensitive. That’s one step up from dogs and cats, I suppose, who lack the red cone and therefore can only see shades of blue and green. Your red-sensitive cone allows you to see not only red, but orange, yellow, and purple. Butterflies have five types of cones in their complex compound eyes, affording them almost the best color vision out there. This allows them to see into the ultraviolet spectrum, and recognize which plants to pollenate.

I don’t like to brag, but I’ve got 16 cones. 16! That means, to imagine seeing the world the way I see it, you’ve got to imagine a color you’ve never seen before, don’t have a name for, and can’t comprehend. Then imagine all the colors derived from that color. Then do that again. Then do that ten more times. Yeah. Some scientists theorize that my excellent color vision is for communication with my fellow mantises. That definitely plays a role, because I actively fluoresce, and that’s how we signal to each other that it’s time to choose a mate. Maybe I also need acute vision to have extremely accurate depth perception, when it’s time to aim to smash my dinner to smithereens… which is, you know, always.

Bottom line is, your human science will never fully understand my glorious eyeballs.

We mantis shrimp come in a couple of different models: smashers and spearers, so to speak. Some of us have long, spiky appendages that ensnare and impale our prey, while others have a giant blunt “club” claw that packs a punch like no other. I strike with a force that is approximately 100 times my own body weight. If you could accelerate your arm at ONE TENTH of that speed, you could throw a baseball off the planet.

What with my club hand, I’m not the best at writing blogs. I’m better at rapping. Check out my debut.


*You can also buy a T-shirt with my face on it, so, that’s pretty awesome.

Mantis Shrimp

Screen Shot 2016-03-29 at 11.20.43 AMMantis Shrimp are neither a shrimp nor a mantis. These odd looking creatures fall under the Subphylum of crustaceans and are in the same class as shrimp, crabs and lobsters. Mantis Shrimp have their own order called Stomatopods, which contains over 450 different species of these animals.

We can separate Mantis Shrimp into two main categories: spearers and smashers. This is in reference to their front appendages. Spearers have an almost spear like appendage that is used to snag soft bodied prey, while smashers have developed a thickened, hammer like appendage used to break shells and exoskeletons. *The Mantis Shrimp seen above is a smashing Mantis Shrimp.

While these animals seem cute and cuddly these are actually one of the most dangerous animals we have the ability to see around Catalina. The Mantis Shrimp will use its smashing and spearing appendages at great speeds to immobilize or kill its prey. The estimated speed at which these animals use their raptorial claws is the same as the acceleration of a .22 caliber bullet or 10,000 times the force of gravity. This movement is so fast that water vaporizes around the claw meaning the Mantis Shrimp’s prey gets hit twice: once by the claw itself and once by the resulting shock wave.

Screen Shot 2016-03-29 at 11.20.19 AMWhile these animals do seem quite dangerous, when seen in the ocean, they will most likely stay hidden within their burrows. Mantis Shrimp create “L-shaped” burrows that conceal their entire body. They will then poke their head out to watch out for predators or to find prey. If you ever observe a Mantis Shrimp the chances are they will retreat into their burrow away from any trouble. However if they do not retreat be wary for the Mantis Shrimp really packs a punch!

Spiny Lobster: Un-mammalian & Totally Alien

Whether protecting our kelp forests through predation, or acting as an enticing entrée on a dinner plate, the California Spiny Lobster is a vital organism for both our ecosystems and our appetites. When compared to mammals, the California Spiny Lobster truly looks other-worldly, like something out of a Guillermo Del Toro movie. Adult male lobster can grow up to 3 feet in length, and weigh 25 pounds. You may notice that they look like bugs of the sea; that is because they belong to the phylum Arthopoda, meaning “jointed limbs”. This phylum is home to many common insects and crustaceans, like spiders, centipedes, and crabs.

Unlike their heavily armed cousins, the American Lobster, California Spiny lobster do not have large claws protruding from their front. Instead they have sharp spines on their carapace for defense, as well as very strong jaws that could deliver a nasty bite. They use their strong jaws to crush open and devour many kelp-eating creatures like sea urchins; therefore lobsters are crucial in maintaining a healthy ecosystem balance. Lobsters can crawl around on the ocean floor in any direction, however while swimming, the lobster can only move backwards. Using their powerful tail, California Spiny Lobster propel themselves backwards into rocks and crevices to hide. Though a quick escape, this defense also makes them effectively blind while retreating from a predator.

Prized for it’s rich meat, the California Spiny Lobster makes up one of the largest sport fisheries on the west coast. Lobster hunters must acquire a California sport fishing license as well as an ocean enhancement stamp in order to catch the appetizing arthropod. There are many regulations to lobster diving such as legal size, number you can catch in one outing, dates that you can gather lobster, and more. These regulations are in place to make the lobster industry as enjoyable and sustainable as possible. Size limits are in place to allow lobsters to grow to a reproductive age. Catch number is regulated so not too many are taken from a habitat. Hunting season dates are in place to make sure lobsters are safe during the time they are carrying eggs and molting. If you have any questions about lobster fishing, you should visit the website for the California Department of Fish and Wildlife at www.dfws.ca.gov.

Both delicious and nutritious. Un-mammalian and totally alien. The California spiny lobster plays a vital role in maintaining a healthy ocean ecosystem as well as supplying us with a delicious dish.


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