Posts Tagged: crab spider
A sure-fire way to frighten arachnophobics is the very mention of "spiders"--especially on Halloween.
Spiders aren't insects but arthropods, order Araneae. They have eight legs, which according to some, are seven legs too many. They are also distinguished by their chelicerae with fangs that inject venom.
You've seen them. Black widow spiders. Jumping spiders. Crab spiders. Garden spiders.
If you fear them, there's a name for that fear: Arachnophobia. Wikipedia says that "People with arachnophobia tend to feel uneasy in any area they believe could harbor spiders or that has visible signs of their presence, such as webs. If arachnophobics see a spider, they may not enter the general vicinity until they have overcome the panic attack that is often associated with their phobia. Some people scream, cry, have trouble breathing, have excessive sweating or even heart trouble when they come in contact with an area near spiders or their webs. In some extreme cases, even a picture or a realistic drawing of a spider can also trigger fear."
The general fallacies, as listed by Rod Crawford, curator of arachnids:
- Spiders are insects.
- "Arachnid" is just a fancy name for spider.
- You can always tell a spider because it has eight legs.
- All spiders make webs.
- The orb web (round or "geometric" web) is a "normal" spider web.
- A "daddy-longlegs" is a kind of spider.
- Most spiders could not bite humans because their fangs are too small.
- Any spider species can be found anywhere.
- All spiders are male.
- Spiders are most numerous in late summer.
- You are never more than three feet from a spider.
- Spiders "suck the juices" of their prey, and do not literally eat it.
- Spiders don't stick to their own webs because their feet are oily.
Meanwhile, over at the Bohart Museum of Entomology at the University of California, Davis, plans are underway for an open house themed "Insect Myths." They will focus on spider myths, too.
The event, free and open to the public, is set for Sunday, Nov. 23 from 1 to 4 p.m. in Room 1124 of the Academic Surge Building on Crocker Lane, off LaRue Road. Directed by Lynn Kimsey, professor of entomology at UC Davis, the museum houses a global collection of nearly eight million specimens and is the home of the seventh largest insect collection in North America, and the California Insect Survey, a storehouse of the insect biodiversity. The museum is open to the public four days a week, Monday through Thursday (9 a.m. to noon and 1 to 5 p.m.) but it sponsors special weekend open houses as well.
The remaining schedule:
- Sunday, Nov. 23: “Insect Myths,” 1 to 4 p.m.
- Saturday, Dec. 20: “Insects and Art,” 1 to 4 p.m.
- Sunday, Jan. 11: “Parasitoid Palooza,” 1 to 4 p.m.
- Sunday, Feb. 8: “Biodiversity Museum Day,” noon to 4 p.m.
- Saturday, March 14: “Pollination Nation,” 1 to 4 p.m.
- Saturday, April 18: UC Davis Picnic Day, 10 a.m. to 3 p.m.
- Sunday, May 17: “Name That Bug! How About Bob?” 1 to 4 p.m.
- Saturday, July 18: “Moth Night,” 8 to 11 p.m.
When you attend the Bohart Museum open houses, you'll probably have the opportunity to hold and/or photograph "Rosie," a 24-year-old tarantula. It's one of the critters in the live "petting zoo," which also includes Madagascar hissing cockroaches, millipedes and walking sticks./h3>/span>
Jumping spider eyes the photographer. (Photo by Kathy Keatley Garvey)
Crab spider on sedum eyes a honey bee. (Photo by Kathy Keatley Garvey)
Garden spider captures a honey bee. (Photo by Kathy Keatley Garvey)
They're ambush predators.
Here you are, a bee, touching down on a flower and little do you know there's a patient and persistent crab spider lying in wait.
Sometimes they're camouflaged, matching the color of a blossom, like a yellow crab spider on a gold coin, or a pinkish-white crab spider on sedum.
But there was no missing this white crab spider on a Mexican sunflower (Tithonia) last weekend. It stood out like a snowy owl perched on a crate of crimson pomegranates.
Crab spiders belong to the family Thomisidae and are often called "flower crab spiders." They're not web weavers or jumping spiders. They're ambush specialists that trap unsuspecting prey.
If you're wondering why some honey bees, leafcutter bees, blue orchard bees or sweat bees don't go home at night, the crab spider is one of the reasons.
Crab spider on a Mexican sunflower, Tithonia. (Photo by Kathy Keatley Garvey)
Crab spider on a gold coin. (Photo by Kathy Keatley Garvey)
Crab spider on sedum. (Photo by Kathy Keatley Garvey)
It was a bad day for a butterfly.
We stopped by the Ruth Risdon Storer Garden, part of the UC Davis Arboretum, at noon today as triple-digit temperatures climbed to a scorching 103.
We spotted a few cabbage white butterflies (Pieris rapae) nectaring the Verbena (Verbena bonariensis), and a few honey bees on the gaura (Onagraceae).
The cabbage whites seemed to like the Verbena. They fluttered around the blossoms gracefully, touching down like snowy princesses in winged gowns and spiked heels, belying the fact that their caterpillars are pests of cabbage, kale, radish and broccoli, mustard and other members of the family Brassicaceae.
One cabbage white, however, wasn't so lucky.
As we rounded a corner of the garden, we noticed it wasn't fluttering. It wasn't moving. It wasn't doing anything.
There was a good reason why it wasn't going anywhere.
A hungry crab spider.
Crab spider with its kill, a cabbage white butterly. (Photo by Kathy Keatley Garvey)
This one got away. (Photo by Kathy Keatley Garvey)
All that glitters is not gold.
The gold coin flowers (Asteriscus maritimus) planted in our yard attract a goodly number of leafcutter bees and hover flies (aka flower flies and syrphid flies).
But if you look closely, gold coins attract something else--arachnids.
This little crab spider (below) blends in so well that at first glance, it's not easy to spot.
And that's the key. Perfectly camouflaged, it awaits prey.
A golden opportunity...
Camouflaged crab spider waits for prey on a gold coin. (Photo by Kathy Keatley Garvey)
Close-up of crab spider camouflaged on gold coin. (Photo by Kathy Keatley Garvey)
It was not a good day for a flower fly.
A flower fly, aka syrphid fly, dropped down in a patch of pink roses at the Häagen-Dazs Honey Bee Haven at UC Davis today to sip nectar.
It was a pink-rose kind of day.
Not for the flower fly, though. A crab spider, lying in wait, pounced.
The battle ended quickly, but the syrphid-fly feast was not to be. Not today. The predator dropped its prey.
You can see lots of predator-prey action at the Häagen-Dazs Honey Bee Haven, a half-acre bee friendly garden located next to the Harry H. Laidlaw Jr. Honey Bee Research Facility on Bee Biology Road, west of the central campus.
It's open from dawn to dusk. Admission is free for all--including predators and their prey.
Crab spider nails a flower fly in the Haagen-Dazs Honey Bee Haven. (Photo by Kathy Keatley Garvey)
Crab spider loses its prey and heads down a stem. (Photo by Kathy Keatley Garvey)