Crab Spider: Discover The Unique Spider Species That Looks Like A Crab

Have you ever come across a spider that resembles a crab? Well, let us introduce you to the fascinating world of crab spiders. These small to medium-sized spiders are named for their crablike appearance and unique ability to walk sideways.

Crab spiders are known for their flat bodies and stout, robust legs. Their front two pairs of legs are longer than the third and fourth pairs, which allows them to easily grab their prey. They can be found in various environments, such as flowers, where they wait patiently to ambush insects that come their way.

So, if you happen to come across a spider that looks like a crab, now you know that it’s likely a crab spider. These intriguing creatures showcase just how diverse and fascinating the world of spiders can be.

Crab Spiders Overview

Crab spiders, belonging to the Thomisidae family, are often mistaken for crabs due to their unique appearance. These spiders, found across North America, possess intriguing features and characteristics. In this section, we’ll explore three specific spider species that closely resemble crabs: Misumena Vatia, Misumenoides Formosipes, and Gasteracantha Cancriformis.

Misumena Vatia

The Misumena Vatia, also known as the flower spider or goldenrod spider, is an arachnid commonly found in North America. To blend in with their environment, these spiders can change color from white to yellow over a span of 10 days, often matching the flowers they reside on. Some key features of the Misumena Vatia include:

  • Red racing stripes
  • White or yellow coloring
  • Crab-like legs

Misumenoides Formosipes

The Misumenoides Formosipes, or whitebanded crab spider, is a small spider species characterized by its whitish-yellow or yellowish-brown color. The carapace of the whitebanded crab spider can appear slightly greenish, with a broad pale yellow midband bordered by two darker, thinner yellowish bands on the sides. Notable characteristics of the Misumenoides Formosipes comprise:

  • Crab-like legs that extend sideways
  • Ability to walk in any direction
  • Typically found in flowers

Gasteracantha Cancriformis

The Gasteracantha Cancriformis, commonly referred to as the spiny orb-weaver or crab-like orb weaver, is another interesting species in the arachnid world. With its flattened, spiny abdomen resembling the shape of a crab’s shell, this spider is truly a sight to behold. Distinctive traits of the Gasteracantha Cancriformis include:

  • Six sharp spines on the abdomen
  • Brightly colored markings
  • Unique web-spinning behavior
Spider Species Coloring Additional Features
Misumena Vatia White, Yellow (can change) Red racing stripes
Misumenoides Formosipes Whitish-yellow, Yellowish-brown Greenish carapace
Gasteracantha Cancriformis Varied, often bright Six spines on abdomen

By exploring these three fascinating spider species (Misumena Vatia, Misumenoides Formosipes, and Gasteracantha Cancriformis), you’ve gained insight into the diverse world of crab-like spiders. The unique features of each species within the Thomisidae family are a testament to the remarkable adaptability and specialization found within the arachnid kingdom.

Physical Characteristics

Color and Appearance

The crab spider is known for its crab-like appearance. The legs extend outward from the sides, allowing them to walk in any direction. In terms of color, these spiders can vary quite a bit. They can be:

  • Whitish-yellow or yellowish-brown
  • Slightly greenish with a broad whitish-yellow midband
  • Yellow-brown with greenish markings

You can also find variations with a red stripe and even some that appear pink or black.

Size and Length

Crab spiders are generally small in size, and their body length can vary depending on the species. Some common sizes you might encounter are:

  • 3/8 inch in length for brown recluses
  • Larger species like the yellow garden spider can have a body length of over an inch

Always remember that their actual size may vary depending on their age or other circumstances.

Exoskeleton Details

The exoskeleton of a crab spider provides essential protection for the spider. Some distinctive features include:

  • Spiny hairs covering the carapace, abdomen, and legs
  • Six eyes arranged in pairs, which is a unique characteristic for certain crab spiders like the brown recluse
  • Dark violin-shape on the cephalothorax (head) in some species

These details help identify different crab spider species in the United States.

Habitat and Distribution

North American Habitats

In North America, crab spiders can be found living in various environments. They are especially common in woodland areas where they blend in among plants and leaf litter. Some species might also reside on tree bark or under rocks. Here are some examples of where you may find crab spiders in the United States:

  • Flowering plants
  • Tree bark
  • Leaf litter
  • Woodlands

South American Habitats

Down in South America, crab spiders have adapted to various habitats as well. From Mexico and Central America down to the southern tip of the continent, these spiders can be found in similar environments to those in North America. The main difference is the types of plants and vegetation these spiders might inhabit. Some South American habitats for crab spiders include:

  • Tropical forests
  • Savannas
  • Grasslands
  • Mountain regions

Caribbean Habitats

In the Caribbean, crab spiders prefer warmer climates where they can reside in various plant species native to the region. The diverse flora of the Caribbean allows crab spiders ample opportunities to camouflage themselves and hunt their prey. A few examples of Caribbean habitats for crab spiders include:

  • Palm trees
  • Coconut trees
  • Flowering shrubs
  • Coastal dunes

Crab spiders have a broad distribution, but their habitats tend to have similar characteristics. These spiders are found in environments where vegetation is abundant, allowing them to blend in and capture prey effectively.

Diet and Prey

Common Prey

Crab spiders, as their name suggests, look like crabs. They mainly feed on insects that are attracted to flowers. They are known for preying on bees, butterflies, and other pollinating insects. In some instances, they might also prey on smaller ant species. Some examples of their preferred prey include:

  • Honey bees
  • Bumblebees
  • Monarch butterflies
  • Swallowtail butterflies

Keep your focus on pollinating insects and remember the diet of crab spiders primarily revolves around them.

Hunting Method and Strategy

Crab spiders use a unique, passive hunting strategy called “ambush predation” to catch their prey. When hunting, a crab spider will position itself among the petals of a colorful flower. Their color-matching ability helps them blend in with their surroundings. As pollinating insects, like bees and butterflies, come to collect nectar from the flowers, the crab spider seizes their prey.

Here are some key features of their hunting strategy:

  • Camouflage: Crab spiders can change their color to effectively blend in with the flower they are using as their hunting ground.
  • Ambush: By staying still and waiting for their prey to approach, crab spiders conserve their energy and remain undetected by their unsuspecting victims.
  • Speed and Strength: When the moment is right, crab spiders quickly grab their prey using their powerful front legs.

In summary, remember that crab spiders attract their prey by camouflaging themselves among flowers. By doing so, you can understand the role that pollinating insects play in the diet of these unique spiders.

Behavior and Lifespan

Ambush Predators

As an ambush predator, crab spiders like the whitebanded crab spider and the northern crab spider use their crab-like legs to walk in any direction, often waiting patiently in flowers for prey. They capture their prey simply by grabbing and biting it.

These invertebrates are venomous, using their fangs to inject toxins into their prey. This venom helps in immobilizing and digesting the prey. Their venom is generally not harmful to humans.

Reproduction and Egg Sac Details

Female crab spiders can be distinguished by their larger size and distinctive markings. Male crab spiders are smaller in size with thinner, longer legs. Mating can occur when a male spider approaches a female and signals his intentions.

Once mating has occurred, the female crab spider will create an egg sac. The egg sac is made of silk, and it serves as a protective container for the eggs. Here are some key features of crab spider egg sacs:

  • Made of silk
  • Can have different shapes and sizes
  • Protects eggs from predators and harsh environmental conditions

After laying the eggs within the sac, the female crab spider takes a protective role by guarding the sac until the spiderlings emerge.

Overall, the behavior and lifespan of crab spiders focus on their role as ambush predators and their reproduction process involving the egg sacs. They are fascinating creatures with unique abilities that help them survive and adapt to their environments.

Related Spider Species

Huntsman Spiders

Huntsman spiders (family Sparassidae) are known for their impressive size and speed. They’re often compared to crabs due to their flattened bodies and long, crab-like legs. Some common species of huntsman spiders include the Golden Huntsman Spider and the Pantropical Huntsman Spider.

Here are some features of huntsman spiders:

  • Flattened bodies
  • Long, crab-like legs
  • Agile and fast moving
  • Non-aggressive

Selenopidae

The Selenopidae family, also known as wall spiders, are another group of spiders that resemble crabs. They have wide, flattened bodies and legs that extend from the sides. These spiders can also walk in any direction, further contributing to their crab-like appearance. Like huntsman spiders, Selenopidae are harmless to humans.

Selenopidae characteristics:

  • Wide, flattened bodies
  • Legs extending from the sides
  • Capable of walking in any direction

Philodromidae

Philodromidae, or running crab spiders, have a more elongated body shape compared to other crab-like spiders. Although not as flattened as huntsman spiders or the Selenopidae family, they still possess the characteristic legs that extend outwards. These spiders are adept at running and camouflaging themselves into their surroundings.

Some features of Philodromidae include:

  • Elongated body shape
  • Outward-extending legs
  • Excellent running and camouflaging abilities

Here is a comparison table of the different crab-like spider families:

Spider Family Body Shape Leg Position Movement
Sparassidae Flattened From the sides Fast, agile
Selenopidae Wide, flattened From the sides Walk in any direction
Philodromidae Elongated, slightly flattened Outward-extending Running, camouflaging

In summary, there are several spider families that possess crab-like features, including the huntsman spiders (Sparassidae), wall spiders (Selenopidae), and the running crab spiders (Philodromidae). Each family has its distinct body shape, leg positioning, and movement capabilities. Understanding these differences can help you better identify and appreciate these unique arachnids.

Identifying Crab Spiders

Spider Identification Basics

When it comes to identifying crab spiders, there are a few key features to look for:

  • Crab-like appearance: Their legs extend outward from the sides, resembling a crab.
  • Unique walking style: They can walk in any direction, similar to a crab’s movement.
  • Varied coloration: Crab spiders can be found in white, yellow, brown, or greenish hues.

These spiders belong to the Thomisidae family and can be difficult to identify by their genus. However, you can still differentiate them based on their physical characteristics and habitats.

Crab Spider Picture Guide

A helpful way to identify crab spiders is by looking at pictures. Comparing them can provide insight into their distinct features. For example:

  1. The whitebanded crab spider (Misumenoides formosipes) is small, with a whitish-yellow or yellowish-brown body and slightly greenish carapace. It has a broad whitish-yellow midband bordered by darker yellowish sides. More information here.
  2. The northern crab spider (Mecaphesa spp.) has spiny hairs covering its body and greenish-yellow or yellow-brown markings. It can be tough to identify, even for experts. Learn more about this spider here.
  3. The flower spider (Misumena vatia), also known as the goldenrod spider or red-spotted crab spider, comes in white or yellow with red racing stripes. They can change color within 10 days to blend in with their surroundings. See images of this spider here.

Remember, always refer to reputable sources for images and information, since crab spider identification can be challenging even for experienced enthusiasts.

Conclusion

In conclusion, you’ve learned about the fascinating whitebanded crab spider, which resembles a crab with its legs extending outward and walking in any direction.

These tiny wonders are commonly found in flowers, capturing their prey by simply grabbing and biting it. Their color can range from whitish-yellow to yellowish-brown with hints of green on the carapace.

Another similar arachnid is the northern crab spider. Similar to the whitebanded crab spider, they have various color combinations and spiny hairs on their body.

We hope you’ve enjoyed this brief introduction to the world of crab spiders and developed an appreciation for their unique adaptations. Remember, spiders play an important role in our ecosystem by controlling insect populations. So, the next time you encounter a crab spider, take a moment to observe its incredible appearance and behavior.

Authors

    by
  • Bugman

    Bugman aka Daniel Marlos has been identifying bugs since 1999. whatsthatbug.com is his passion project and it has helped millions of readers identify the bug that has been bugging them for over two decades. You can reach out to him through our Contact Page.

  • Piyushi Dhir

    Piyushi is a nature lover, blogger and traveler at heart. She lives in beautiful Canada with her family. Piyushi is an animal lover and loves to write about all creatures.

22 thoughts on “Crab Spider: Discover The Unique Spider Species That Looks Like A Crab”

  1. Cd, poor spider… I’m from Honduras and I’m an active protector of all wild species in my country, It’s saddening how most people in my country disregard life so easilly. Personally I’ve always wanted to see one of these Giant Crab Spiders but haven’t had any luck in any of our islands.

    Thank you for the picture now I am certain we have these.

    Best regards,

    Medjai

    Reply
  2. Spotted one of these while showering in my home here in Comayagua last night… Nearly scared me to death – it reacted in a fearful manner as well.
    I didn’t snap a picture of it, I have been hunting the internet all day today trying to find out if I was in danger or just overly cautious for nothing.
    Two of my step-children saw it, told me it was a tarantula and ran away. (After my step-son shoved his sister, my youngest step-child, towards the spider to which she reacted with terror and ran as fast as she could.)
    My wife asked me why I didn’t kill it and I _mostly_ jokingly said because it could probably block my attack and get the upper-hand on me…

    I made deliberate, non-aggressive movement to reach my shampoo and body wash and closed the door tightly. I then completed my shower, and very gingerly opened the door to see if the spider was gone before putting my soaps away… I didn’t see it and so of course my arachnaphobic brain kicked in and the hair on my legs started tingling… I poured some extra water on my feet and ran inside.

    Turns out, after researching this thing and finding this page and several other images that matched, my wife realized I am less macho than she thought, haha. Oh well, at least I didn’t kill it and it can continue eating all the bugs around the yard for us. πŸ™‚

    Reply
    • Thanks for the very amusing comment. Huntsman Spiders are shy, nocturnal hunters, and they are not considered dangerous to humans.

      Reply
  3. Spotted one of these while showering in my home here in Comayagua last night… Nearly scared me to death – it reacted in a fearful manner as well.
    I didn’t snap a picture of it, I have been hunting the internet all day today trying to find out if I was in danger or just overly cautious for nothing.
    Two of my step-children saw it, told me it was a tarantula and ran away. (After my step-son shoved his sister, my youngest step-child, towards the spider to which she reacted with terror and ran as fast as she could.)
    My wife asked me why I didn’t kill it and I _mostly_ jokingly said because it could probably block my attack and get the upper-hand on me…

    I made deliberate, non-aggressive movement to reach my shampoo and body wash and closed the door tightly. I then completed my shower, and very gingerly opened the door to see if the spider was gone before putting my soaps away… I didn’t see it and so of course my arachnaphobic brain kicked in and the hair on my legs started tingling… I poured some extra water on my feet and ran inside.

    Turns out, after researching this thing and finding this page and several other images that matched, my wife realized I am less macho than she thought, haha. Oh well, at least I didn’t kill it and it can continue eating all the bugs around the yard for us. πŸ™‚

    Reply
  4. I come bearing photographic evidence of a much smaller, definitely same classification, of spider as the one that left me if stunned fear. πŸ™‚

    This guy is ~5-6x smaller than the first one I encountered, which was a major relief. However, the picture is blurry and oddly lit because he decided to visit our indoor bathroom and so I used a laptop for lighting and my DROID MOTO X as a camera.

    I made the assumption of male vs. female based on size difference. (It is extreme in my two sightings.)
    Sadly the large one has not returned. She may have been just as creeped out by me, in the end. – I wanted a picture to show off… πŸ™

    http://imgur.com/yYJtTdq — This is a cropped picture. I have nothing for size comparison, but it is about the size of an American Half-Dollar coin from long ago.
    This is indoors. Behind our bathroom door.

    Reply
  5. I come bearing photographic evidence of a much smaller, definitely same classification, of spider as the one that left me if stunned fear. πŸ™‚

    This guy is ~5-6x smaller than the first one I encountered, which was a major relief. However, the picture is blurry and oddly lit because he decided to visit our indoor bathroom and so I used a laptop for lighting and my DROID MOTO X as a camera.

    I made the assumption of male vs. female based on size difference. (It is extreme in my two sightings.)
    Sadly the large one has not returned. She may have been just as creeped out by me, in the end. – I wanted a picture to show off… πŸ™

    http://imgur.com/yYJtTdq — This is a cropped picture. I have nothing for size comparison, but it is about the size of an American Half-Dollar coin from long ago.
    This is indoors. Behind our bathroom door.

    Reply
  6. Yet another sighting of the smaller one. πŸ™‚ He is missing a leg now. Not sure if this was the case on the first encounter or not. This time MUCH closer than I would normally be comfortable with.
    Again, outside for a shower. This time it was 0830 here in Comayagua and he was under the bowl we use for scooping water from the “pila”(sp?) (large water basin, with laundry ripple thing).

    I picked it up, not paying any mind to that spot as I was scooping out dead bugs… turn to my left to place the bowl down and their sits ol’ 7 legs… He ran from me and I coaxed him up the wall. He cleaned himself, watched me shower and was gone by the time the soap was rinsed from my hair/face.

    I have pictures but imgur.com is down it appears… Oh well, not close enough to see details anyway. Just bizarre to see it in daylight.

    Reply
  7. Yet another sighting of the smaller one. πŸ™‚ He is missing a leg now. Not sure if this was the case on the first encounter or not. This time MUCH closer than I would normally be comfortable with.
    Again, outside for a shower. This time it was 0830 here in Comayagua and he was under the bowl we use for scooping water from the “pila”(sp?) (large water basin, with laundry ripple thing).

    I picked it up, not paying any mind to that spot as I was scooping out dead bugs… turn to my left to place the bowl down and their sits ol’ 7 legs… He ran from me and I coaxed him up the wall. He cleaned himself, watched me shower and was gone by the time the soap was rinsed from my hair/face.

    I have pictures but imgur.com is down it appears… Oh well, not close enough to see details anyway. Just bizarre to see it in daylight.

    Reply
  8. My husband and are moving into a different house on Nevis. We noticed there are literally hundreds of “holes” in our yard, yes, hundreds. We were then told they are the homes of the “donkey spider” im not in to wiping out a species, but I’m equally not sure if I can actually live with hundreds of these hairy guests. any ideas?

    Reply
    • We hope this does not come off as glib, but if you know that you cannot live with the native wildlife, and you know that the wildlife is present, and you know you do not want to wipe out a species, we don’t understand what makes this new home so desirable. We have been doing some additional research into the Donkey Spider, and we now believe the individual pictured in this posting is not the true Donkey Spider, which is a common name for a Caribbean Tarantula. Tarantulas are not aggressive spiders, and we would urge peaceful cohabitation. The individual in this posting is a Huntsman Spider or Giant Crab Spider and they do not live in holes in the ground.

      Reply
  9. Good afternoon,
    It was only after leasing the property and doing landscaping/cleanup prior to move in did I notice the holes. That being said, it probably wouldn’t have kept me from moving in, I was told by a neighbor that the holes belonged to ‘tarantulas’ and another stated they were donkey spiders. I am a geologist and also have a degree in wild life biology, so I’m used to common names not being accurate. I haven’t seen one of the spiders yet, as we haven’t moved in. I will post a pic when I can photograph one. The property has been empty for a couple of years, with only minimal upkeep. I’m hopeful once the debris is cleared and the dogs and cats are patrolling the outside, the majority of the spiders will find a more quite location.

    Reply
  10. Good afternoon,
    It was only after leasing the property and doing landscaping/cleanup prior to move in did I notice the holes. That being said, it probably wouldn’t have kept me from moving in, I was told by a neighbor that the holes belonged to ‘tarantulas’ and another stated they were donkey spiders. I am a geologist and also have a degree in wild life biology, so I’m used to common names not being accurate. I haven’t seen one of the spiders yet, as we haven’t moved in. I will post a pic when I can photograph one. The property has been empty for a couple of years, with only minimal upkeep. I’m hopeful once the debris is cleared and the dogs and cats are patrolling the outside, the majority of the spiders will find a more quite location.

    Reply
  11. As to the donkey spider comment, they are tarantula’s, but as everything in St. Kitts Nevis has a nickname, so do the tarantula’s. You will find numerous holes that they live in, but I’ve lived here for over 7 years and rarely do I see one. Maybe when it rains torrentially which isn’t happening now. There are also land crabs that will make large holes in the ground. Also, very rarely seen. Now if only I could find a photo of the spiders I have been seeing lately, I would be happy. I am very freaked out by spiders and haven’t seen these huge red spiders that I found in my bathroom and unfortunately my shower one evening. Even if it doesn’t have a nasty bite, I don’t want it in my house! Where would I find more photo’s so I can identify it and find out more about it?

    Reply
    • We have an extensive archive and a pretty decent search engine. We will also attempt to provide you with an answer.

      Reply
    • Check out whip spiders. I lived in St. Kitts in the 80s, and my first night in our new home, I encountered one. Scariest thing I’ve ever seen, but I’ve learned that they are totally harmless. They don’t even bite. But they look like Lucifer himself!!

      Reply
  12. I don’t care what kind of a spider of that it is, and it’s not ugly and not pleasant too look at it and is big enough to eat a new born puppy, My husband and I is from the Quam and used too tell me stories about the Island, before the he pasted away, Glenn,said that he saw very little few spider’s during his lifetime there

    Reply
  13. I lived on Guam and 92. I didn’t see very many spiders except in the jungle. Most of what I saw in or around my place was cute little geckos

    Reply
  14. I captured one running around my house.
    Built it a nice little home while winter passes. She seems to enjoy flys a lot.
    About 3 weeks ago she started to make a sack out of this web like material. 3 days of working and she sealed her self inside the sack. I’m wondering how long she will be in there.
    I’m from gold canyon arizona. About 15-20 minutes from MESA Arizona.

    Reply
    • If she is hibernating, she will likely emerge when the weather is more suitable. If she is guarding eggs, she will probably emerge when the spiderlings are ready to disperse. Either way, we suspect not more than a few months.

      Reply
  15. I captured one running around my house.
    Built it a nice little home while winter passes. She seems to enjoy flys a lot.
    About 3 weeks ago she started to make a sack out of this web like material. 3 days of working and she sealed her self inside the sack. I’m wondering how long she will be in there.
    I’m from gold canyon arizona. About 15-20 minutes from MESA Arizona.

    Reply

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