Thursday, April 30, 2015

A New Little Friend!

When I was young, Mrs. Crawford across the street used to beckon me over, saying, "Come here! I've found another one of your little friends!" She'd be digging around in her roses, usually, and there would be a snake, or a spider, or some other fascinating life-form indigenous to planet Earth.

Well, today, as I was at my computer, grinding away at my freelance stuff, Sue climbed the stairs to my little garret office and said, "You should see this interesting bug on the window downstairs!"

And there I was again, hustling across the street to see what Mrs. Crawford had dug up . . .

At first glance, I thought, Oh, honey, it's just a lacewing . . . But a little closer inspection, and I realized: No! This is one of those really, really cool insects I've been wanting to see in, like, forever!

It's a mantisfly!

See how its forelegs are modified into little "raptorial" clawed arms? Much like a praying mantis. The head is triangular, too, and with big eyes. Note how those forelegs are attached way forward on the body, well away from where the other four legs attach. And look how long the prothorax is (the thing that looks like a neck). (It kind of reminds me of a snakefly I found on the curtains of a motel room in Tehachapi, California, one time . . .)

If I am lucky in my simplistic identification attempt, this nifty creature is a green mantisfly, Zeugomantispa minuta. See here in BugGuide, a website I couldn't live without. (Well, okay, I could live without BugGuide, but it really does beat most printed insect field guides, if you are starting out with a little basic knowledge about arthropods. Like, if you know what an "arthropod" is, you'll be able to use it. But I digress. As usual.)

It was only about 1/2 inch long, including the wings, which it kept folded down its back, and it really did look a lot like a green lacewing. But you know? It didn't move like one. It walked on its four hind legs, like a miniature mantis.

Here it is, grooming one of its antennae. One of the forelegs is extended, so you can see the little claw it uses to grab little insects with.

This, my friends, is one of those nifty insects you see when you flip through your field guide, and you go, "Whoa! What a wild-looking creature! I wonder where you go to see those crazy things!? Those are in North America? Geez . . . !"

Yes, this is one of those insects that inspire movie monsters. That make you think, "There's no end to the diversity of life on Earth." That make you grateful you have eyes, that you're here, that you got to see it.

It was quite a delicate creature. Apparently they only ever reach about 3/4 inch long. And get this! The larvae eat spider eggs! That probably explains why this one was on our sunporch: Spiders like to build webs in the window sills. (We try to keep up with it, but you know . . .)

It's really fascinating: This is one of those insects whose first instar (life stage, molt) is quite active, which has agency. As soon as it hatches from amid its egg cluster, the larva moves off in search of a spider egg sac. When it finds one, it bores inside and eats the eggs. (In some species, the hatchling mantisflies look around for adult spiders, climb aboard like a hitchhiker, then transfer to the egg sac once it's spun.) Once the egg sac is entered, the larval stages are actually less "developed" than that first one, that had to seek the egg sac/spider. This particular variation of the insect life cycle is called hypermetamorphosis.

What a fascinating find!