I had a post in draft form wherein I mentioned that I was keeping my eye on the egg case of the Chinese mantises (Tenodera aridifolia sinensis,) figuring it was due to erupt at any time. This morning, that post was ruined.
I was just about to head off to meet with a student when I took a last look at the egg case, and found it almost literally dripping with newborn mantids. I quickly got the camera out of the car and did a quick, impromptu photo session, toying briefly with the idea of calling the student and postponing slightly. I decided to keep to schedule, so I shot in natural (brilliant) sunlight, trusting to the camera’s exposure meter, which was not the best of choices. I was using a different camera with, apparently, radically different base settings for contrast and exposure – believe it or not, this is at a setting with contrast and saturation intentionally lowered, specifically to use in bright conditions, and it was still off the scale. I tweaked the image a bit in Photoshop to make it more presentable, but this is far from what I would have liked to have captured.
Still, this is the first time I’ve gotten the actual emergence, and by the time I returned the action was over, so at least I have these. In the center of the image, marking the top of the swarming babbies, three mantids can be seen emerging from the egg case, which has the consistency of styrofoam, or maybe that expanding foam insulation stuff. They would draw themselves out like worms, legs held tight against their bodies, and stretch the legs out once free to slowly crawl down and join the mass of siblings, where they would pause for a bit to allow their chitin to dry and harden. One earlier emergent can be seen at the top of the egg case, scampering around cockily, while the hind end of another appears behind the emerging three. The dark spots are their eyes, and this hatching gave me a little more of a baseline in using their coloration as a guide, as we’ll see shortly.
Here’s another view, as one plays daredevil off to the side. Notice how the heads have swollen after hatching, with the eyes becoming prominent. The whole mass was writing slowly in an insectily creepy way, and every once in a while one of the firstborns would scamper up or down the column excitedly. I am not, at this point, sure of what exactly they’re hanging from; while it could be each other, right now there’s also a string of some kind of debris hanging from the egg case, so perhaps they were using that.
When I’d returned about four hours later, the young’uns had dispersed throughout the bush, and it took a few moments of careful examination to even spot one – then, abruptly, there would be several visible. They measure 10mm long at this point, and their coloration has become more what we’d expect, though they still stand out against the darkness of the azalea leaves. Their eyes have now blended in with their bodies, giving an indication that if you’ve found any with dark eyes, they really are newly hatched.
Considering that on March 7th, and again on the 18th, this egg case was coated in ice during the freezing rain storms, it’s somewhat weird that these guys are out now – not because they’ve weathered the cold, but because it doesn’t seem like winter’s actually past yet. I’m cool with all the signs of spring that are apparent now, including the first hummingbirds at the feeder, and it’s interesting to watch the ongoing family tree develop – this is the third generation of this genetic line that I’ve watched here. There are also the green lynx spiderlings still to be found, which I’ll be watching develop – most of these are a few meters away on the rosemary bush.
And then, there’s another generation soon to appear, and I’m going to horrify a lot of people by saying I have no intention of interfering, and hope to see the hatching. This will be a lot harder though, since mama put her egg sac under a wooden box out of sight, so I have to overturn the box to check on progress, something that I don’t want to do too often because I’d prefer not to disturb them frequently. Still, now that the egg case has appeared, I suspect the black widow mother will stay put regardless, and the newborns should be along pretty soon themselves. And yes, I’m almost positive this is the same one photographed last year. I’ll be sure to post any images of those babbies when they appear too, so you have that to look forward to. And should, because they look quite a bit different from the adult phase. Keep watching this space…
