- Author: Kathy Keatley Garvey
In and around Vacaville, we've seen them on olive trees, honeysuckle vines, passionflower vines, and wooden stakes. On the UC Davis campus, we've seen them on a 10-foot-tall Mexican grass tree (Dasylirion longissimum) in the Storer Garden, UC Davis Arboretum and Public Garden.
Then last week we spotted an ootheca on our decades-old weathered barn birdhouse.
It appears that a predator, probably a bird, ravaged it, though.
But those oothecas are tough.
As Wikpedia tells us: "Oothecae are made up of structural proteins and tanning agents that cause the protein to harden around the eggs, providing protection and stability. The production of ootheca convergently evolved across numerous insect species due to a selection for protection from parasites and other forms of predation, as the complex structure of the shell casing provides an evolutionary reproductive advantage (although the fitness and lifespan also depend on other factors such as the temperature of the incubating ootheca."
"The ootheca protects the eggs from microorganisms, parasitoids, predators, and weather; the ootheca maintains a stable water balance through variation in its surface, as it is porous in dry climates to protect against desiccation, and smooth in wet climates to protect against oversaturation," according to Wikipedia. "Its composition and appearance vary depending on species and environment."
We've always liked old barns. On our family farm, we spent many a glorious moment jumping around in the haymow before, after or during our chores. Fun times! Yes, we heard all the barn-related comments then and now:
- Close the door! Were you born in a barn?
- No use closing the barn door after the horse is gone.
- That guy couldn't hit the broad side of a barn.
Well, that praying mantis that graced us with the ootheca? Odds are that the offspring weren't born in a barn. Neither did they eclose.
- Author: Kathy Keatley Garvey
We rarely see an adult praying mantis until late summer or fall.
Their offspring are out there, though.
And sometimes we see life go full circle.
On Sept. 23, 2018, we watched a Mama Stagmomantis limbata, as identified by UC Davis entomology student and mantis expert Lohit Garikipati, a Bohart Museum of Entomology associate who rears mantids) grace our planter with an ootheca in Vacaville, Calif.
As we mentioned in a previous Bug Squad blog:
"She climbed a redwood stake, looked around, saw me (oh, no problem, you're not a predator!), and crawled over to the other side. She positioned herself upside down, bulging abdomen intact, and proceeded to do her business. A frothy cream-colored substance began to emerge. (See my short YouTube video.) When darkness fell, she was still there."
"When Monday dawned, she was still there, her ootheca finished and hardening. It probably contains several hundred eggs, but who's counting? However, scientists estimate that only one fifth will survive to adulthood. Many of the nymphs will be eaten by their hungry brothers and sisters. Bon appétit!"
Fast forward to May 13, 2019. We spotted an offspring cradled in a leaf a few inches from the ootheca. "First-instar, Stagmomantis limbata," Garikipati said. "Must be an ooth nearby."
And then on May 19 our "star"--or maybe one of its siblings--came up missing a chunk of its abdomen. Sibling cannibalism?
No "sisterly or brotherly love," to be sure.
- Author: Kathy Keatley Garvey
Talk about the unexpected.
“Look!” says Jim.
He pauses by the kitchen counter.
"Over there!” he says, pointing. I don't see anything except the half-filled coffee pot.
Then I see it. "There," as in “over there,” is a praying mantis clinging to the wall and staring at us. It is like finding a grizzly bear in Kenya. (Yes, there is a grizzly bear in Kenya, on a private reserve, the Ol Jogi wildlife conservancy in Laikipia, Kenya)
Praying mantis expert Lohit Garikipati, entomology student at the University of California, Davis and an associate at the Bohart Museum of Entomology, identified our kitchen guest as a Stagmomantis limbata, a bordered mantis native to North America. “Looks like she wanted to come in for some free food!” Lohit quipped.
That's how we acquired Henrietta (which means home ruler) . Apparently she hitched a ride on the back of Jim's jacket as he was removing a patch of Mexican sunflowers. She opted to depart her "ride" in our kitchen.
By the half-filled coffee pot. Praying mantids don't do coffee.
We placed Henrietta in an aquarium, screened at the top, and kept her for a week, feeding her drone flies and crickets. We provided her with an upright stick just in case she wanted to deposit an egg case, an ootheca.
She did.
Several days later an ootheca, about an inch long, appeared in the aquarium. Not on the stick—she chose to deposit it on the floor.
What does an ootheca look like under a powerful microscope? Amazing. Lynn Epstein, UC Davis emeritus professor of plant pathology, photographed it with a Leica DVM6 microscope owned by the Department of Pathology and the College of Agricultural and Environmental Sciences (see below).
- Author: Kathy Keatley Garvey
She hides 'em and we seek 'em.
We've spotted as many as seven adult praying mantids at a time in our little pollinator garden in Vacaville, Calif., but never once have we seen any of them laying eggs.
Until now.
The praying mantis lays an egg mass known as an ootheca or a protective egg sac. But always when you're nowhere around!
Not so this time.
Late Sunday afternoon, Sept. 23, Ms. Mantis (a Stagmomantis limbata, as identified by UC Davis student Lohit Garikipati, a Bohart Museum of Entomology associate who rears mantids) decided to grace our milkweed planter with a little present.
She climbed a redwood stake, looked around, saw me (oh, no problem, you're not a predator!), and crawled over to the other side. She positioned herself upside down, bulging abdomen intact, and proceeded to do her business. A frothy cream-colored substance began to emerge. (See my short YouTube video.) When darkness fell, she was still there.
When Monday dawned, she was still there, her ootheca finished and hardening. It probably contains several hundred eggs, but who's counting? However, scientists estimate that only one fifth will survive to adulthood. Many of the nymphs will be eaten by their hungry brothers and sisters. Bon appétit?
"Now that she's deposited the ootheca, will she expire soon?" we asked Garikipati.
"It's still early on in the season, so she may lay another two or three," he said.
She may indeed. Mama Mantis continues to hang out in the milkweed, while her ootheca, like a flag on a flag pole, "commemorates" the spot.
It should be a warning sign to incoming monarchs.
The next day, we found the clipped wing of a male monarch.
- Author: Kathy Keatley Garvey
Surprise! Surprise!
You never know what you'll see when you're strolling through the 100-acre UC Davis Arboretum and Public Garden, a treasure to students, faculty, staff and visitors.
Case in point: For the last several months, we've been admiring a Mexican grass tree, Dasylirion longissimum, a 10-foot tall drought-tolerant plant with long, needle-like leaves radiating from its trunk. So perfect. So exquisite. Kinetic art at its finest. Indeed, it's often described as an "architectural wonder" in the plant world. Scores of horticulturists in California and the southwest United States favor it as their focal point for their xeriscape landscape projects.
The plant is native to the Chihuahuan Desert, which extends from West Texas, through parts of New Mexico and Arizona, and into much of the central and northern portions of the Mexican Plateau. It can tower 15 feet in height.
Last week we noticed something different about its presence in the UC Davis Arboretum: a brown clump clinging to the faded green wiry spikes.
Could it be? It was. A praying mantis egg case or ootheca.
To protect it from "egg gatherers," we won't indicate the exact location. But it is clear evidence that a female praying mantis was there and she, no doubt, ambushed and devoured honey bees, syrphid flies and butterflies before mating and producing the egg case.
Mantis expert Andrew Pfeifer, administrator of the popular Facebook page, "Mantis Keepers," says the ooth appears to be the work of a Stagmomantis limbata.
California has only a handful of mantid species, Pfeifer says. The natives include Stagmomantis limbata, Stagmomantis californica and Litaneutria minor. Introduced ones: Mantis religiosa, Tenodera sinensis and Iris oratoria. “Typically you have pockets for native species where you see only one,” he says.
We usually begin seeing sizable mantids around July and continuing through October. We photographed this one, a Stagmomantis limbata, perched on showy milkweed (Asclepias speciosa) on Oct. 3, 2017 in Vacaville, Calif., as she nailed unsuspecting prey. In this case, a honey bee.
Her egg case is probably around somewhere....but she didn't lay it on our milkweed....or our Mexican grass tree....