The Brown Recluse Spider

The brown recluse spider (scientific name: loxosceles reclusa, also commonly called the brown fiddleback spider) can look formidable, especially one that has full grown to having a body ¾ inch long. The it’s long legs make it look imposing. But they get the name ‘recluse’ due to their natural tendency to avoid contact, especially with people.  The brown recluse is a non-aggressive spider, that only bites out of defense.

Identifying the Brown Recluse

Unlike most spiders which have eight eyes, the brown recluse spider has only six, two in front, two on the sides and two in the back. Since it lives in dark secluded places and prowls around at night, it doesn’t need to see very much. Its other senses suffice.

As you might expect, the brown recluse is brown. Some say it resembles a violin, Maybe you will join me in thinking that likeness takes a little imagination. You might live a long time near some brown recluse spiders without seeing one, but because of the size of a fully mature brown recluse, when you see one you will be impressed.

(click on an image to enlarge)

A Brown Recluse Brown Recluse Spider A Brown Recluse Spider (closeup)

Brown Recluse Spider Habitat

Brown Recluse Habitat in the U.S.The brown recluse likes some human habitations and they can be found in wood piles, sheds, cellars, garages, dark closets, under beds, and other places where it is dry and not often disturbed. They like cardboard, some humans say, because it resembles tree bark. They might be found in shoes that haven’t been worn recently, behind baseboards, behind pictures, near to furnaces.

As their name suggests, the brown recluse spiders are reclusive and they prefer to stay out of the way and out of sight. The brown recluse builds a web, mostly as a hiding place, not as an insect trap. This web will be in some dark corner and it will not be very fancy.

Almost all the American brown recluse spiders are to be found in the southern part of the middle of the United States. Not many are ever found along the Atlantic or Pacific Coasts. Not many are ever seen in the Rocky Mountains or the Northern Appalachians.

Brown Recluse Spider Food

At night this spider goes roaming around for food. Unlike most other spiders, the brown recluse spider is not picky about eating insects that have died somewhere along their way. They don’t have to be the killer of their food.

In addition to looking for food, the male brown recluse spider will go looking for females to mate with at night. The female will lay 40 to 50 eggs inside a coat of gray silk about 2/3 inch long. Each female brown recluse spider may produce several coats with eggs in a month. As you can see, given enough other dead bugs to eat and plenty of dark nooks and crannies, a rambling house with few human inhabitants can gain a substantial spider population.

The Fearsome Black Widow Spider

Few spiders have a well deserved notoriety to match the black widow. Everyone knows that the female will get her eggs fertilized and then eat the male, thus becoming a widow. While this may happen to most such spider couples, it is not necessarily the universal rule. Ever so many stories and movies have been inspired by this model of behavior.

The black widow’s shiny black body is very distinct, which makes them very easy to identify.  A mature female may be an inch and a half in length, including moderate length legs. Both males and females have shiny black bodies with a relatively big black abdomen. Only that female spiders abdomen will have the distinctive red hourglass-shaped spot. If you ever see a male, you will notice it is smaller and it might be lighter in color and have a red or pale brown stripe in the abdomen.

Black Widow Spider
Black Widow Spider

Black widows are definitely web spiders. The silk glands located at the back of the abdomen provide for prolific web building. Oil on the legs of the black widows make it possible for them to hike around on the web without getting entangled themselves.   They build webs to capture insects that might be flying or crawling by. Their poison will kill the captured meal. The typical procedure of excreting digestive fluids to dissolve the prey bit-by-bit and then taking in the partially digested food follows the capture.

A young adult black widow will go through a winter in out buildings, cellars, or other sheltered places. It will have been hatched from an egg ball of 100 to 400 eggs. It might have eaten several brothers or sisters in order stay alive. Remember the doctrine of survival of the fittest. It is a strong belief among black widow spiders. Females can live for five years and produce eggs each year after the first.

In the late spring of each season the surviving spiders will pair off and conduct a protracted courtship activity prior to mating. A mature male will spin a sperm web and deposit sperm in it. He then will load some of the sperm on his antennae and deposit them into the female. When mating is completed the female eats the male and starts laying eggs.

The female deposits her fertilized eggs into a globular silken container in which they remain camouflaged and guarded. She might construct 5 to 15 of the egg balls during a season. All the time she has to be tending her web and capturing prey to support the massive egg production that has to take place in the summer.

It may take 20 to 30 days before the eggs hatch. Maturation may take four to six months. The newly hatched spiders each strive to grow enough to survive the coming winter. As they do this they might eat or be eaten by a close relative or by some other spider.

Black Widow Habitat

Black widows can be found in most of the Western Hemisphere. Three groups of black widows in the United States, northern, southern, and western have some minor distinctions. The southern, by far the most numerous, thrives in the warmer climates and is most often encountered.

Black Widow Spider Bite and Venom

Our other article has more information about black widow spider bites and treatment.