This order of insects is very diverse and non-conforming! The smallest insect and the largest brood known are found in parasitic wasps. According to Grissell, “the largest insect egg, the most spectacular matings, and the largest sexual orgies are found in bees.” He also states that ants have the highest heat tolerance, the most toxic venom, and are the fastest.
Hymenoptera are the 2nd largest insect order in the world, yet it is estimated there are up to 2.5 million species in this order that haven’t been studied. Hymenoptera perform some very important functions in our world and pollinate about 1/3 of all the food we eat. Of all the insects in this order, about 75% of them feed on other insects; think about how important this is to the world!! They are also great at recycling nutrients into our soils.
No matter what facts are known about the Hymenoptera, there will always be an exception. When studying this order, one must just expect that nothing will be true of all those in one family, much less in one genus! Even the name Hymenoptera has possible double meanings: ptera is “wing” in Greek but is the prefix hymen which means “membranous” or hymeno which means “the god of marriage.” Both will work since one structural aspect of Hymenoptera is the forewing and backwing are connected by a hook.
Hymenoptera larvae are not mobile. When the female lays the egg or eggs, they/it must be where that larvae will need to feed or they larvae nest must be provisioned. Other interesting aspects of bees, wasps, and ants is that in some cases a single egg can produce more than one larva and they can produce even if they are not mated. The length of time that larvae remain in this stage is determined by the temperature; many will overwinter as larvae. Queens will also overwinter.
Forty-seven families of this order, about 76,000 species, are referred to as parasitoid rather than parasitic. This difference is between most parasites are much smaller than their hosts and may not always kill their host. A parasitoid always kills the host and is about the same size as the host. Interestingly, parasitoids are mostly attracted to plants with small flowers, such as Golden Alexanders (Zizia aurea). Plants with larger flowers attract the larger Hymenoptera, such as bees. Both are attracted to colors and scents. Predatory wasps differ vastly, not only in the insects they feed their young but also in other biological ways.
It’s very difficult to ID a wasp from a photo alone. What a wasp is hunting and where it lives helps with figuring out what species it is. Solitary wasps are defined by these 2 aspects. Predatory wasps are defined by their ovipositor and try to form, some predatory wasps are pollen-collectors and not predatory at all!
Although many of us are familiar with the social aspects of bees and ants, most adults of this order are solitary. The sole purpose of males is to mate and most females have no maternal responsibilities once they have laid their eggs.
I have broken this order into three sets: Ants, Bees, Sawflies, and Wasps. I think this will make it easier to see whole collections of a similar group of insects.