Sunday, January 15, 2023

Red-Headed Centipede


If mother nature could create a creature to star in a horror movie, it would certainly be the giant centipede. This creepy crawly is the stuff of nightmares for many and fascination for others. Missouri is home to many types of centipedes and millipedes, and one of the most magnificent centipede found in our state is the Giant Red Headed Centipede. These impressively large centipedes are only found in a few scant counties in Southern and Southwestern Missouri, particularly near the Arkansas state line.

 They are commonly mistaken for millipedes.... the most common way to tell the difference between the two is to look at the legs. All centipedes have odd numbered pairs of legs and only one pair of legs per body segment. Millipedes always have two pairs of legs per body segment. The knick-name of hundred-legger comes from the impression of hundreds of tiny little legs all moving in an undulated movement that is almost mesmerizing. Centipedes in fact do not possess anywhere near one thousand legs, but one can certainly understand how the knick-name came to be. Centipedes tend to have a flattened body whereas millipedes are more rounded. Millipedes lack venom, although some species can emit a chemical from their legs that can cause skin irritation. Centipedes are very defensive by nature and quick to bite if handled, millipedes on the other hand do not bite. Another difference between them is diet. Millipedes eat organic matter found on the forest floor or in whichever habitats they live, whereas centipedes are carnivores. Centipedes are predators and feed on a broad diet of insects, and spiders. They are fond of pinkie mice, small snakes, and small amphibians too. These centipedes have excellent eyesight which aids them in hunting down prey. They are also fast-moving creatures and little escapes their notice or their grasp. Millipedes tend to live life in the slow lane. 

This particular species of giant centipede varies in color by location, in Missouri they are unmistakable with a black body, 21 to 23 pairs of yellow legs and a reddish head. This color is referred to as aposematic coloring and offers a warning to would-be predators that they are potentially dangerous. Humans should especially heed this warning, as they can and will bite if handled. They have front legs that are modified fangs. It has been reported that the legs of this species can leave tiny punctures in the skin, and each leg contains venom that can be dropped into each wound. This can cause inflammation and irritation

 According to one story cited by Dr. Baerg, an officer in the Confederate Army, while sleeping in his tent, was suddenly aroused by the creepy feeling of a large centipede crawling on his chest. A number of spots of deep red, forming a broad streak, indicated the arthropod’s passage across the man’s chest and abdomen. Violent pain and convulsions soon set in, accompanied by excessive swelling in the bitten area. The victim fought with death for two days and then succumbed. The agony suffered by the bitten officer was described by an eyewitness as the most frightful he had ever observed. The famed arthropod scientist J. L. Cloudsley-Thompson once explained that “centipedes seem to exert a weird fascination on the morbid appetites of the hysterical and insane.”

 A reaction to the venom of a centipede such as this officer experienced would have been rare even in the 1860’s, and continues to be a rarity today. Nearly all centipede bites are harmless, painful yes, but nonetheless harmless in terms of its impact on your health. Most compare the pain level to that of being stung by a yellowjacket or a hornet. Certainly not something we want to experience, but not likely to kill us. We all know there are exceptions to every rule, for those with allergies to the protein in the venom, a bite can become very serious. Always monitor how you feel whenever anything bites you, if you aren’t feeling well, get to medical help immediately.


These centipedes commonly reach lengths up to 6 1/2 inches, but lengths of 8 inches have been reported. They are found on rocky hillsides, glade habitats, under logs, stones and other protected locations. They are rarely encountered by humans because of their secretive nature, but should you come across one you won't soon forget the experience. In years past I have owned one of these centipedes, and I can honestly say it is one of the few invertebrates that give me the pause.


These centipedes have excellent eyesight which aids them in hunting down prey. They are also fast-moving creatures and very little escapes their notice or their grasp. Occasionally predators such as rodents, other small mammals, spiders and birds feed on these centipedes. These must be the daring dieters! Centipedes have developed a useful way to distract a predator. They drop a limb; a leg literally falls off. This detached leg will continue to wiggle and distract the hungry predator long enough for the centipede to make a hasty retreat. After multiple molts, the lost leg will begin to regrow. Pretty ingenious in you ask me.

 Female centipedes lay eggs in rotting wood and will guard the eggs by wrapping her body around them. When the eggs hatch she will continue to stay with her offspring and look after them for a short period of time. This parental care is unusual among arthropods. The offspring will look similar to the adult, except they are lighter in color and have fewer legs. They will gain the adult coloration and proper amount of legs as they age.

 For obvious reasons these fast-moving, somewhat intimidating creatures are not for everyone. No judgment here. Fortunately they come packed in a relatively small package (when compared to an elephant lets say), and are rarely encountered by squeamish humans. These beneficial arthropods consume vast amounts of insects, and for those with arachnophobia, they have a special fondness for spiders. They are quick to feed on small rodents thus removing the little vermin from our midst. At the end of the day it’s about appreciating the diversity that is nature and celebrating even her most creepy creations.


Sunday, January 1, 2023

Northern Black Widow

Black Widows may be one of the most feared spiders in North America. The fear of spiders is one of the top ten phobias in the World and when it comes to spiders that humans view as dangerous, like the widow, that fear seems to be magnified. Their bite is highly venomous and can be extremely painful however it is rarely deadly except in the incredibly young, the elderly or in immune compromised individuals. With their glossy black body and legs, bulbous abdomen, and red hourglass, it is a spider we learn early in life to recognize. Their venom is roughly fifteen times stronger than a rattlesnake! Thankfully, they are also 1,000 times smaller and can only deliver minute amounts of venom with each bite. There is an old saying “the dose makes the venom” and this is especially true of black widow venom, she can control how much venom she delivers, and since most bites are defensive in nature, she is unlikely to use substantial amounts of venom when she does bite. It would be counterproductive to her survival. It takes energy to make venom, and food to make energy and venom to kill and consume her food in order to acquire energy to continue hunting, so you can see that wasting venom to warn us away would not benefit her at all.

Consider the black widow spider. It is a timid little beastie, useful and, for my taste, the prettiest of the arachnids, with its shiny patent-leather finish and its red hourglass trademark. But the poor thing has the fatal misfortune of possessing enormously too much power for its size. So, everybody kills it on sight. --- Robert A. Heinlein

Black Widows are secretive and elusive spiders. The species pictured here (Northern widow) generally builds their webs under rocks or logs in open woodlands or rocky glades. If approached they are quick to run for cover. These are not aggressive spiders and will only bite if provoked or caught between your skin and your clothing or if accidentally touched. Males are capable of biting; however, it is ONLY the female who delivers the venom. The venom contains a powerful neurotoxin and bites can lead to stomach upset, cramps, abdominal pain, sweating, headache, muscle tightness or soreness, delayed pain at the bite sight, and swelling of the hands, feet, or eyelids. Swelling at the sight of the bite is rare. Reactions to their bite can last for several days and may require medical treatment for relief. Most human fatalities due to Black Widow bites occur in the Southwestern United States where larger populations of these spiders exist. While the risk of death exists, it is extremely low. There are over three hundred million people living in the United States, and approximately 2,500 black widow bites reported annually and only about four are fatal. While any death is unfortunate and a loss to be sure, the reality is their bite is rarely fatal, in fact you are more likely to die from an allergic reaction to a bee sting, which claims over fifty lives annually.

These are beautiful spiders, and part of their mystic may come from the fact that they are so highly venomous and potentially dangerous. There is no need to be afraid of these spiders, merely be aware of their possible medically significant bite and avoid contact with them if at all possible. If you have them in your basements, sheds, cellars or anywhere you may frequently encounter them, you might want to consider removing them, especially if you have small children at home. When cleaning in areas where they have been seen always wear gloves. They generally only leave their web when looking for a new place to construct another web. Because of their habit of staying close to their web, encounters by humans are rare in Missouri. Encounters generally happen when we put our hands in places where this shy, secretive spider lives. This particular species is most often found away from human dwellings, which makes it even more unlikely we will come in contact with one.

There are two species that live statewide in Missouri; the first being the common black widow which is found in more southern counties and the Northern black widow is found in more central and northern counties. We encountered both species at Truman Lake where we were camping, I found two common widows within their webs at the bathhouse. Each time I approached I was only able catch a brief glimpse of them before they darted behind the trim board their webs were attached to. They were smaller than the Northern Widow that I photographed here, which was found on a rocky glade we had been hiking.

Juvenile female
Mating takes place in late summer or early fall when males cautiously approach the web where the female is residing. He will tap out a dance on the web to get her attention. If she deems him a worthy mate a new generation will arrive within a couple of months. If not, she may decide he would make a nutritional meal. The reality is cannibalism is rare in natural settings. The males generally have ample opportunity to escape the rath or appetite of the female. In lab settings where spiders are kept in confined cages, and in close contact with each other cannibalism is far more likely and probably where the notion came from that black widows always consume their mate. The female will produce multiple egg sacs each containing more than two hundred eggs. Spiderlings are notorious for dining on their siblings, no brotherly love there! To help thwart this behavior black widows lay eggs that are all identical in size, hatching at the same time into identically sized offspring. This gives each spiderling a fighting chance to escape and live out their spidery lives. If larger spiderlings hatched first, they would consume all their smaller, newly hatched siblings, thus drastically reducing the prodigy the female leaves as her legacy. Spiderlings already have the odds stacked against them, as many predators feed on small spiders, including other spiders, insects, birds, and frogs to name a few. Mother nature gave the black widow an edge in the survival department.

 While many people feel the natural habitat of any spider is under the covers of our beds or some other unwanted location in our homes, as this is often where we are startled by an unwanted encounter with one. This can certainly make us jump and give us the shivers, especially if that visitor is the dreaded widow of exaggerated folklore. In truth they generally live in their own microhabitat created of strong silk, hidden away from our prying eyes and any possible confrontation with us. 

The good that these spiders provide by eating untold amounts of insects far outweighs any danger that may exist from this spider.