Southern Black Widow tending her nest above my porch

I just got home and happened to look up into the corner of my porch today, when what do I see but a Northern Black Widow (Latrodectus variolus) tending her egg case above my steps.

I have seen hundreds of black widows at my house (see some really cool closeups in my previous post on black widows). Normally they are down low, barely above the ground, peeking out from leaves or tree roots. Occasionally I’ll see them hanging beneath my porch steps. But this is the first time I’ve seen one elevated so high. My guess is that she is only roosting so high for the sake of her eggs.

Hanging up high instead of down low

Below is a cool video I took of a black widow I caught this summer.  As mentioned before, the widows I’ve seen in North Carolina are the Northern Back Widow (Latrodectus variolus), and not the Southern Black Widow (Latrodectus mactans), though it is my understanding that their neurotoxin venoms are equally dangerous. That being said, bites are extremely rare and deaths rarer. They are very unaggressive in my own experience and will instantly hide when approached. I usually just note their locations and leave them alone. This girl, however, is not long for this earth. Too close to my door, and I don’t want the babies working their way inside. Plus, my wife is terrified that we have so many widows around to begin with. If it’s any consolation to you insect/arachnid lovers, I am usually much kinder and appreciative of our six- and eight-legged cousins than most.

You can tell the species apart by the fact that Southern Black Widow has a complete abdominal hourglass, while Northern Black Widows have a “broken” hourglass (see the movie below and this previous post).

Also, if you like cool spider videos, check out this Golden Garden Spider video I took.

Northern Black Widow videos:

For your own edification, here is a bit about their venom from wikipedia:

The venom spreads rapidly throughout the body and acts by causing the release of the neurotransmitters acetylcholine, norepinephrine, and GABA.

And symptoms:

During the first 24 hours after a bite:

• Severe pain in muscle groups local to the bite.
• Muscle cramping, primarily in the abdomen, back and thighs.
• Headache, dizziness, tremors, salivation, diaphoresis (excessive sweating), nausea and vomiting.
• Anxiety, fatigue, insomnia.
• Lacrimation (tearing of the eyes).
• Migratory arthralgia (joint pain).
• Tachycardia (rapid heart beat), bradycardia (very slow heart beat), restlessness, hypertension (elevated blood pressure), Tachypnea (hyperventilation).

In some rare and extreme cases, severe complications can arise:

• Spontaneous abortion, preterm labor
• Priapism
• Acute renal failure (failing of kidney function).
• Myocarditis, rhabdomyolysis, paralysis.
• Shock, coma, and death.

Symptoms that may be present at or near the wound:

• Rash, slight erythema (redness of skin), Piloerection (goose bumps).
• Mild edema (swelling due to excess fluid).
• Lesion or mild infection (rare).