In Which I Discover an Ootheca

I was quietly watering the newly installed bed of fava bean seedlings that runs in a narrow strip along the back fence, when I noticed an odd protuberance from one of the fence boards. Our neighbor put up the fence just a few months ago so it still has the blond coloring of unfinished lumber. The strange little outcropping was the same color as the wood and could easily have been a knot hole or imperfection, but something about it made me look closer. It reflected light with the subtle luminosity of something alive.

To the touch it felt delicate and vulnerable -- not like wood at all, more like very fragile Styrofoam. Oval, about an inch long, with fine ridges and a large ridge down the middle like a zipper, it was firmly attached to the fence. Ahh, a new backyard mystery. What could it be?

Touching it triggered some long dormant memory of the praying mantis egg cases we kids used to find back in Virginia, along with a comical image of my mother flapping a dishcloth at swarms of tiny mantis nymphs that had just hatched out in our kitchen, hanging in wiggly green streamers from the cupboards and window ledges. We never found the egg case or figured out how it ended up in the kitchen. Clearly, an egg-laying mantis is resourceful.

The egg cases of memory were rounded and usually discovered adhering to a twig. This modern California version felt the same but looked quite different. Perhaps mantis resourcefulness includes adapting the shape of the egg case to the available surface.

On the hollyhocks only a few feet from the spot on the fence, I had recently seen a large pale green mantis with characteristic folded front legs, elongated body, narrow triangular face and bulbous eyes. The first one I had ever seen in this yard, it was gone by the time I came back with a camera.

On the internet it didn't take long at all to find photos of mantis egg cases that look exactly like the mystery object. As a bonus, I acquired a new word and a bit more insight into the whole process. The case is called an ootheca from the Greek roots for "egg" and "purse" or "pouch". It's the kind of word that carries a built in exclamation. "Ooooh, look at that, an ooooootheca!"

The mama mantis extrudes a lot of soft foamy goo to enclose her eggs. The goo hardens and becomes the ootheca, which keeps the brood safe through the winter until spring comes and hatching occurs. Evidently she can do this several times, so I am keeping my eyes open!!