- Author: Kathy Keatley Garvey
Yes! It's among dozens of fact sheets (mostly insects but some arachnids and other non-insects) posted on the Bohart Museum website. All can be accessed and downloaded at no charge.
Lynn Kimsey, director of the Bohart Museum and a UC Davis professor of entomology, writes the fact sheets, including this one, titled "Widow Spiders."
"Widows are large, distinctive spiders in the genus Latrodectus," Kimsey writes. The Latrodectus mactans or black widow is found throughout the world in warmer regions, while the brown widow, L. geometricus, is found in warmer parts of the United States, including California.
You'll find widow spiders in and around homes, garages, barns and other human-made structures in California. "They build a tough, messy-looking three dimensional web in or behind objects in secluded and protected locations," Kimsey relates.
"During the summer months they may also commonly be found outside under shrubs, and other garden plants, or near porch lights," she says. "These spiders are excellent at controlling insects, particularly flies and crickets. They do not particularly like feeding on cockroaches, but will do so when other insects are unavailable."
What most folks seem to want to know about them are the bites. How painful and toxic are they?
"All spiders have painful and sometimes dangerous neurotoxic bites, but often give dry bites, with no venom," Kimsey points out. "In fact these are the only spiders in the United States with neurotoxic venom. The bites cause extreme physical discomfort and illness for several days to a week and can only be treated symptomatically. Common symptoms include pain in the vicinity of the bite, muscle aches, severe abdominal pain, vomiting, muscular cramping, sweating, fever and head- ache. The bite location itself may go unnoticed."
"There is usually no swelling at the site of the bite, where a small necrotic lesion may form, which heals slowly over a period of weeks or months. Black widow bites are rarely life threatening but may be dangerous for small children or individuals with chronic health problems. There have been no deaths from the bite of this spider for decades. Black widow bites can be dangerous for pets and can be fatal to small dogs or cats."
Kimsey advises that control is not necessary "unless a black widow is in an area frequented by people, particularly children, or by pets. It is important to remember that these are very shy spiders and never bite unless physically threatened."
Noted spider authority Jason Bond, the Evert and Marion Schlinger Endowed Chair in Insect Systematics, UC Davis Department of Entomology and Nematology and his lab usually present a program at the Bohart Museum on spiders at least once a year or engage with folks at the open houses.
The Bohart Museum of Entomology, located in Room 1124 of the Academic Surge Building on Crocker Lane, UC Davis campus, is the home of nearly 8 million insect specimens, plus a live "petting zoo" (Madagascar hissing cockroaches, walking sticks and tarantulas) and a gift shop. The Bohart is temporarily closed due to the COVID-19 pandemic but the online gift shop is open, where you can find insect-themed t-shirts, hoodies, jewelry, posters, books, pens, and stuffed animal toys, as well as insect-collecting equipment.
- Author: Kathy Keatley Garvey
Sometimes it's found in a parade, where the "fear" turns to cheers and applause.
Take the case of the 40-foot black widow spider--yes, 40-foot spider!--that the UC Davis Entomology Club entered in the 103rd annual UC Davis Picnic Parade on Saturday, April 22.
The spider drew oohs and aahs from the crowd, and judges selected it the winner of the “Best Organization” category. It continued to draw oohs and aahs when the club showcased it in front of Briggs Hall on Picnic Day. Thousands of visitors stopped to look or capture photos with their families or take selfies. Little kids just stood and stared. "What's that, Mommy?"
What a spider! And complete with that distinguishing red hourglass marking.
“We built it three years ago,” related president Maia Lundy. “This year we just had to clean it up and make some modifications, like adding ventilation. It took us two meetings --or about 4 hours- of work this year. When we originally built it, we met several times over about a month to finish it. It's made out of plastic sheeting, chicken wire, pvc pipe, pool noodles, window screening, and held together by lots of duct tape and zip ties!”
The spider came to life in the backyard of entomologists Robert and Lynn Kimsey of the UC Davis Department of Entomology and Nematology faculty. Robert Kimsey, a forensic entomologist, serves as the club's advisor. Lynn directs the Bohart Museum of Entomology. Her specialty is wasps, but she answers all kinds of questions about insects and arachnids at the Bohart Museum.
The black widow spider is no stranger to the parade. It's reminiscent of the one that the UC Davis Entomology Club built for the parade about 25 years ago.
The Entomology Club decided to revive the project in 2015. It all took place in the Kimsey yard, and Robert Kimsey offered a blow-by-blow account then as he watched it develop from plastic sheeting to a black widow spider. “It is huge and currently in pieces as it is getting its skin and pedipalps and other minor body parts and whatnot. It is anatomically correct in every way! The students have been trained well in arachnology!”
“There are legs all over the place,” Kimsey said of the eight legs, each slightly less than 20 feet long. In real life, the body of the black widow spans about 1.5 inches long.
Kimsey said membership in the entomology club is open to all interested persons, including faculty, staff, college and high school students and community residents. (Contact entomologyclub@gmail.com.) President Maia Lundy heads the club with Jamie Fong, vice president; Andre Poon, treasurer; Lovey Corniel, secretary; and Chloe Shott, vice secretary.
As for black widow spiders, yes, the bite is venomous. The glands contain the neurotoxin, latrotoxin, which causes the condition latrodectism, both named after the genus, according to Wikipedia. "The female black widow has unusually large venom glands and its bite can be particularly harmful to humans. However, despite the genus' notoriety, Latrodectus bites are rarely fatal. Only female bites are dangerous to humans."
Take a bow, UC Davis Entomology Club. Well done! The prize: a certificate and a glass trophy.
The black widow spider joined seven other parade award winners:
- Best Community Entry: Davis Whymcycle Society
- Most Spirited: DEVO (Davis Enology and Viticulture Organization)
- Best Theme: Biological and Agricultural Engineering
- Best Animal Entry: Canine Companions for Independence
- Best Department Entry: UC Davis School of Veterinary Medicine
- Best Organization: Entomology Club
- Parade Marshal's Choice: Bakuhatsu Taiko Dan
- Parade Participants' Choice: West Plainfield 4-H Club, Woodland
- Author: Kathy Keatley Garvey
This just in for Halloween!
Ever seen a false black widow spider?
Commonly known as the cupboard spider, it's a semi-cosmopolitan spider that's often confused with the "real" black widow spider, known for its powerful venom.
Adrienne Shapiro of Davis took this photo (below) of a spider on the Shapiro property (photographed and released). Her husband, Art, distinguished professor of evolution and ecology, identified it as a female false black widow, Steatoda grossa.
"The overall appearance is very similar to the real thing, except it lacks the red spot on the belly and usually--but not always--has some yellow patterning on the dorsal abdomen: a crescent-like line at the anterior end and a row of triangular spots down the midline, visible here," Shapiro commented.
"But a few may be all black, or the yellow is barely visible," he noted. "This is a semi-cosmopolitan species usually found in or around buildings. It's originally from the Mediterranean region and in the United States and is mostly urban-bicoastal, absent from the heartland. Its habits are nearly identical to the black widow. It's not very common and I personally have never seen it in Davis before. The bite of the female IS venomous, but not to the degree a true black widow bite is. The symptoms are usually local pain, redness and blistering, but some people report generalized malaise for up to a couple of days. I am unaware of any deaths or serious sequelae."
Steve Heydon, senior museum scientist at the Bohart Museum of Entomology, UC Davis, says he gets a few calls about the false black widow. "Steatoda mostly lives under things on the ground," he said, "while the black widows live a little bit off the ground."
We've never seen the false black widow, but have seen numerous black widows (genus Latrodectus.) One black widow homesteaded on the rim of our swimming pool several years ago and we managed to photograph Mama straddling her egg cases. The familiar red hourglass was definitely visible!
The black widow's bite, particularly harmful to people, contains neurotoxin latrotoxin, which causes the condition latrodectism, both named for the genus. Only the female bite is harmful. But the bite is rarely fatal to humans.
We watched Mama scurry around, seemingly trying to protect both egg cases simultaneously from the long-lensed camera.
She was like a Mama Grizzly protecting her cubs.
- Author: Kathy Keatley Garvey
You'd never know that if you looked in the backyard of UC Davis entomologists Robert and Lynn Kimsey.
The UC Davis Entomology Club, advised by Robert Kimsey, is building a 40-foot-long black widow spider for the UC Davis Picnic Day Parade on Saturday, April 18.
Latrodectus hesperus has never looked so...well...huge!
And so colorful--right down to the distinctive red hourglass.
What's it like seeing a huge spider coming to life in your backyard?
“Well, it is very weird!” said Robert Kimsey, a forensic entomologist and longtime advisor of the club. “It is huge and currently in pieces as it is getting its skin and pedipalps and other minor body parts and whatnot. It is anatomically correct in every way! The students have been trained well in arachnology!”
“There are legs all over the place,” Kimsey said. Each is slightly less than 20 feet long. "Again, it is huge. I have to admit that there are some brilliant artists and engineers in this group! But looking out the windows into the backyard takes your breath away. Any non-biologist would completely go to pieces.”
Along with anyone suffering from arachnophobia.
The last time the the UC Davis Entomology Club entered a float in the UC Davis Picnic Day Parade was about 20 years ago. And yes, it was a black widow spider (see photo below)
“The spider idea collectively came from all members of the cabinet after hearing about past picnic days from Bob,” said Entomology Club vice president Alex Nguyen. “When we presented it to the club we received very positive feedback so we decided to commit to marching in the parade with a float this year.”
The spider represents a month of planning and two weeks of building, Nguyen said.
During the parade, Entomology Club president Marko Marrero will be inside the spider, hoisting it up, and walking with it, along with two people at each leg.
If you want to see the spider, the opening ceremony of the parade begins at 9:25 a.m. in the grandstands on the North Quad Avenue across from Wickson Hall. The parade begins at 10, snakes downtown, and ends at noon. Announcement locations include the beginning of the parade; second and D Street in downtown Davis; F street in front of PDQ Fingerprinting; and third and C Street in downtown Davis.
You can also see the spider after the parade. It will be showcased in front of Briggs Hall, off Kleiber Hall Drive, where scores of entomological events will take place, including cockroach races, maggot art, honey tasting, and fly-tying. There will be a bee observation hive, ant displays, and displays of mosquitoes, forest insects and aquatic insects.
The UC Davis Entomology Club and the Entomology Graduate Student Association will be working the booths, along with faculty and staff.
Membership in the UC Davis Entomology Club is open to all interested persons (email entomologyclub@gmail.com). Members are faculty, staff, students (college and high school) and community residents.
They have at least one thing in common: they're interested in insects and other arthropods, including arachnids (spiders).
Even at picnics...and parades...
- Author: Kathy Keatley Garvey
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."
So many myths about spiders. The Burke Museum of Natural History and Culture, University of Washington, Seattle, has posted some of the myths, misconceptions and superstitions on its website.
The general fallacies, as listed by Rod Crawford, curator of arachnids:
General Fallacies
- 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.
