OCTOBER
1998

 

 

 

By
Tom Turpin
 
Professor of
Entomology
Purdue University

 

 

 

 

 

10-08-98

Some Insects Ghoulish Enough for Halloween

All Hallow's Eve traditionally has been a time when all sorts of ghoulish creatures wander the earth. Ghosts, goblins, disfigured humans, werewolves and headless horsemen all have roamed freely on this night. Add in a few real creatures that are sometimes kind of creepy-bats, black cats and spiders for instance-and Halloween is downright scary.

Spiders certainly have characteristics that qualify them for inclusion in this scary celebration. They are predators, sucking the juices from the prey entrapped in their webs. And those webs! Who enjoys running into a spider web in the dark? (Or the light for that matter.) Then, there is the black widow spider, who has earned her name because of her predilection to make a meal of her husband after mating. Now that is Halloween behavior!

But if spiders are creepy enough to be Halloween stars, why not insects? After all, insects do some really gross things, too. The praying mantid, in spite of its reverent name, isn't. Like the black widow, the female mantid seems to delight in chewing off the head of her mate.

Of course, all of us have supplied blood to the real werewolves of this world: mosquitoes. And some of us have been so unlucky to supply blood to bed bugs. These insects got their name because they are like ghosts. They hide during the day and come out under the cover of dark to suck blood from their human victims.

Don't forget some of the predatory true bugs that feed by sucking the juices out of their prey through fearsome beaks. Some appropriately are called assassin bugs because of the way they destroy their insect meals. One of these bugs feeds on humans. It takes blood from the human victim when the human is asleep. It frequently attacks the human around the mouth and is dubbed the kissing bug!

But the most ghoulish of the insects would have to be some flies. A few flies have taken to laying their eggs on living animals. The eggs hatch into maggots that begin to feed in the host.

One such group of flies is known as bot flies. These insects are large, stout-bodied flies that resemble bees. The sheep bot actually deposits larvae directly in the nostrils of sheep. These larvae feed in the sinuses of the sheep until full grown. At this time, the sheep snots the larvae from its nostrils. Occasionally, the sheep bot makes a mistake and deposits a larva in the nostril of a human-a very unpleasant experience, according to those who have been unfortunate enough to have been afflicted.

There are also rabbit bots, horse bots, mouse bots and a human bot. The human bot feeds under the skin and takes about 50 days to complete development.

A fairly common bot attacks cattle. The adult cattle bot fly also is called a heel fly since it lays eggs on the target animal. Cattle are frightened by the bots flying around their legs. They respond by running around with their tails in the air in a futile attempt to escape. That behavior is called gading; hence, these flies are sometimes dubbed gad flies.

The cattle run for good reason. Once the fly lays her eggs, the young larvae burrow in the skin and move through the inside of the cow toward the windpipe. From there, it is onward and upward to the back of the animal. At this point, the maggot chews a hole in the cow's hide and drops to the ground to pupate. There are references to the cattle bot in humans, and like in cattle, the larvae migrate through the human before emerging through the skin.

Another ghoulish fly is the screwworm fly. This fly lays eggs on a live animal, and the maggots begin to eat the animal. Such feeding makes the screwworm a major pest of livestock. There also have been reports of screwworm larvae in humans. In one such report from 1883, a physician recovered 250 maggots from the nose of a human victim. You can't get much more Halloweenish that that!

 

Writer: Tom Turpin
Editor: Olivia Maddox