The local common name for these social wasps is marimbondo-chapéu in Portuguese or hat wasp in English. The name refers to the form of the nest, seen above.
Seen from below, I’d say it looks more like a sunflower. They are really packed in there. I’d estimate there are probably a couple of hundred of them.
Here’s another crop that I like of that same image.
You’ve probably noticed by now these images were taken during the day. So what are all of them doing hanging out on the nest? Taking a siesta? I wondered the same thing. I spent around 45 minutes taking pictures and attempting to gauge just how closely I could approach without alarming them. During that whole time, not a single one flew off or arrived.
I began to wonder if these wasps might be nocturnal. When I returned a few hours after dark, I had my answer. At that point, the nest was quite active, with dozens flying around. A quick internet search for “nocturnal wasps Brazil” gave me the genus, Apoica, a genus known for its nocturnal habits.
When reviewing the images, I noticed they have relatively large ocelli, which undoubtedly helps them navigate and find prey at night.
Most of these photos were taken with my 100mm macro, sometimes combined with my teleconverter. The closest I ventured was for this habitat shot, taken with my wide angle zoom at its widest 18mm setting.
I don’t have my copy of Latin American Insects with me, but I just checked it via google books. Hogue refers to this genus as parasol wasps, also because of the shape of the nest. He notes that only the common species, Apoica pallens, has a yellow abdomen.
by Charles L. Hogue