Ant Lions

As a child my parents were into nature and the living things there. We didn't just learn that it was a Blue Jay, but we learned something about the lives of Blue Jays. We collected shells in tide pools along the Pacific Coast and learned about all the other sea life in those pools of water. We learned about trees and reptiles, and of course we learned to observe and enjoy insects. One of the things we discovered on our walks was little circular pits in the soil in sandy areas, and if you tossed an ant into that depression you would elicit a response from something buried in the sand at the very bottom. As the ant attempted to scramble back out of that little pit the dry sand would crumble beneath its feet, making it very difficult for the ant to escape. And, as bits of that sand rolled to the bottom there suddenly would be little explosions of sand being flung out by the hidden creature. Bits of sand would continue to be tossed out, and with luck and time the ant would eventually tumble all the way to the bottom, where it was rather rudely grasped and pulled out of sight into the sand at the bottom.

 

This is the Ant Lion, the larva of another of the beneficial insects in nature. The predatory larva is also referred to as a "doodlebug", and really is rather goofy looking with its out-of-proportion body attached to a very narrow thorax and head, and with jaws that would seem far to large to manage, but obviously are there for some useful purpose. The name of "doodle" bug, however, comes from the meandering patterns the larvae may create on the surface of the sand as it crawls about seeking just the right place in the sand in which to make its pit. Once the site is chosen, where the sand is fine and dry, the larva begins by pushing itself backward in a circle, and as it continues to circle the beginnings of the pit are established. As it digs deeper into the sand the doodlebug uses its head to throw sand out of the pit, and in as little as just 15 minutes it is able to create the pit about one inch deep and perhaps two inches in diameter at the top. Now it rests, buried in the sand at the very bottom with just its tiny head and massive jaws exposed, waiting for that meal of an ant to drop in.

The ant which does fall into the pit and is captured in the jaws of the doodlebug is quickly subdued by a bit of venom that is injected from the jaws of the doodlebug. The saliva of the doodlebug then flows through its hollow mandibles to dissolve the insides of the ant, leaving just the exoskeleton of the ant behind. The empty exoskeleton of the ant is then, rather unceremoniously, flung back out of the pit with the same motion of the doodlebug's head that was used to fling the sand. Many other small arthropods are eaten as well, such as small spiders, when they too stumble into the ant lion pit. The body of the ant lion larva is covered with bristly hairs, many of them facing toward its head, and these help to anchor this predator in the sand so that the struggling prey cannot drag it out. If you decide you want to take a peek at the ant lion itself you can take a spoon and scoop out some of the sand right at the bottom. However, when it is disturbed the ant lion becomes immobile, and covered with sand as it is you might just overlook it.

 

The doodlebug moves through several stages as the larva, and eventually is ready to become the adult insect. Its life as the larva may last for anywhere from one to three years, possibly dependent upon its food supply and how quickly it is able to grow. Once ready, though, the larva uses silk from glands at the end of its abdomen and creates a silken cocoon for itself. Within this it moves to the third stage of its life, the pupa, and within the pupa it now transforms to the adult insect. This process may take several weeks, and during that time the sand-covered cocoon is buried deep in the soil. Once the moment of adulthood is close the pupa burrows out of its cocoon and heads to the surface, where the adult insect now emerges. Adult male and female ant lions mate, the female lays eggs back in sandy areas, and the process begins again. It is not unheard of for an ant lion adult to, ironically, be captured and consumed by an ant lion larva.

The adult ant lion would seem to be far less fascinating than in its odd early life as the larva. The insect family of ant lions is called Myrmeleontidae, and it falls within a larger grouping of insects called the Neuroptera, or "nerve winged" insects. The long wings of these adult insects are interlaced with fine veins to give them that name. The adult ant lion looks very much like a damselfly, which is a type of dragonfly, but has a very weak, fluttering flight. The antennae of ant lions are longer than those of damselflies and the eyes are much smaller. Ant lions also are active at night, and often may be found on the walls of your home by the porch lights. They are completely harmless to people and pets and should not be harmed by us. Apparently the adults are not predators, instead feeding on nectar or pollen, or possibly not feeding at all in the adult stage. Their primary purpose, as it is for so many adult insects, is to produce the next generation.

Just how many different kinds of ant lions are there? Like so many other topics it is interesting the variety of answers you may find for this question. Internet references state anywhere from 65 to 100 different species in North America, and from 2000 to 5000 species known throughout the world. Let's just say that in the U.S. we likely have nearly 100 different kinds, with the vast majority of them living in the more arid habitats of the Southwest states. Most species are a pale, rather drab grayish color, but some kinds supplement that with darker spots and patterns on their wings. Most kinds are medium sized, with their narrow bodies about 1.5 inches long and a wingspan of about 2 inches. However, in Arizona you may find one enormous species, whose wings easily stretch out to 5 inches and whose body may approach 4 inches from nose to tail. However, no matter how big and gruesome these guys may seem, they are still harmless to people while serving the benefit of eating ants, spiders, and other crawling bugs.