Currently viewing the category: "Cobweb Spiders"
What's That Bug? does not endorse extermination

Subject:  Strange-Looking Spider
Geographic location of the bug:  Tamshiyacu Tahuayo Regional Conservation Area, Loreto, Peru
Date: 06/15/2018
Time: 10:51 PM EDT
Your letter to the bugman:  Hello-
I was in Peru last month and found this unique-looking spider in my canoe. It is definitely a spider, as it used a silk dropline and had its body divided into two distinct parts (it only had 7 legs, but I suspect it originally had 8 and lost one). I am at an utter loss to what species it is. Would you please be able to help identify it? I apologize for the lack of a better-quality picture.
How you want your letter signed:  Captain Nemesis

Whip Spider

Dear Captain Nemesis,
This is quite an unusual looking Spider.  It reminds us of of the Scorpion Tailed Spider from Australia, though we do not believe your individual is in the Orbweaver family.  We are posting your image while we attempt to identify your unusual Spider.  Perhaps Cesar Crash of Insetologia will recognize it.

Update:  Thanks to Karl who submitted a comment identifying this as a Whip Spider in the genus Ariamnes, and providing a link to pBaseArachnidos de Centroamerica also has a matching image.


What's That Bug? does not endorse extermination

Subject:  What’s in my web?
Geographic location of the bug:  Camarillo, Ca near succulents
Date: 05/07/2018
Time: 07:53 PM EDT
Your letter to the bugman:  Dear Bugman,
I was outdoors enjoying some fresh air and succulents  and noticed a pretty substantial spider web plus these very interesting white spiky spheres. I’m wondering if you can identify them?
How you want your letter signed:  Melanie on the Irish Chain

Brown Widow Egg Sacs

Dear Melanie on the Irish Chain,
These are the Egg Sacs of a Brown Widow Spider, a species recently introduced to North America from Africa.  The Brown Widow is a relative of the native Western Black Widow, and since the introduction of the Brown Widow, populations of native Western Black Widows seem to have diminished, perhaps being displaced by a more competitive relative.

What's That Bug? does not endorse extermination

Subject:  Is this a black widow?
Geographic location of the bug:  Northern Michigan
Date: 10/21/2017
Time: 02:29 PM EDT
Found this creature inside my home 10/21/2017.  Is this an immature female black widow? It had the red spots on the back and some on the abdomen. We also found this one the the porch in early October. Is it an orb weaver?
How you want your letter signed:  J.E.

Immature, female Northern Black Widow

Dear J.W.,
This is most certainly an immature, female Widow Spider, and considering your location, it is most likely an immature, female Northern Black Widow,
Latrodectus variolus, which is pictured on BugGuide.  Your other spider is indeed an Orbweaver.

What's That Bug? does not endorse extermination

Subject:  Not a black widow, or is it?
Geographic location of the bug:  Apartment in eastern Massachusetts
Date: 10/17/2017
Time: 07:04 PM EDT
I found this odd looking spider in my apartment. My first thought was black widow, given its shape and the pattern on its back, but the coloration is different. What is this spider?
How you want your letter signed:  Joe

Cobweb Spider

Dear Joe,
Though your image is quite blurry, we concur that this does look like a Widow in the genus
Latrodectus, and we believe it might be a highly variable Brown Widow, a species recently introduced from Africa.  According to BugGuide data, it has been reported from nearby Maryland, and in Southern California in recent years it has nearly supplanted the native Black Widow.   While we entertain that possibility, we think this is more likely a harmless member of the Cobweb Spider family, like possibly Steatoda triangulosa which is pictured on BugGuide.

Update:  October 22, 2017
Thank you. We’ve gotten a picture of one of these spiders’ underside and observed their behavior a bit. They’re aggressive if their webs are disturbed, and roll into a ball if they fall. The webs themselves are messy and thee-dimensional, but not really funnel shaped.
Does this affect the identification?

Cobweb Spider

Hi Joe,
We agree with Cesar Crash who provided a comment that this is NOT a Brown Widow, and most likely a harmless Cobweb Spider.  Your new image confirms that conclusion.

What's That Bug? does not endorse extermination

Subject:  Tiny spider found near farm
Geographic location of the bug:  Blacksburg, VA
Date: 10/10/2017
Time: 11:01 AM EDT
I found this spider near a farm. Caught it in a jar and it laid its eggs, and now looks a lot more deflated. What species could she be? Thanks.
How you want your letter signed:  Daniel

Dewdrop Spider

Dear Daniel,
This is a kleptoparasitic Dewdrop Spider, probably
Argyrodes pluto, which according to BugGuide has a range of “USA – From Maryland, Virginia, Missouri, southwest to Chihuahua and Jamaica.”  Kleptoparasites steal food from other species.  According to BugGuide:  “Argyrodes spiders (and related genera) are kleptoparasitic. They live in the outer edges of other spiders’ webs and move in to steal prey when the coast is clear. Apparently the method of at least one species (Argyrodes nephilae) is to attach a line of silk then cut the wrapped prey out of the host web. The bundle swings free and can be taken to the outskirts of the main web to be eaten in relative safety.”

What's That Bug? does not endorse extermination

Subject:  Black Widow Spiders
Geographic location of the bug:  Northern New Mexico
Date: 10/04/2017
Time: 12:05 AM EDT
Good evening.
I moved to Santa Fe from Southern Oregon four months ago for work and I have never encountered female black widow spiders like this. We have killed eight large, female specimens in the house over the past two days.  Most of them were on the move in broad daylight, and surprisingly aggressive.  Two of them were actively sharing a web.  I captured one in my bathroom, and confirmed the red hour glass. I’ve never known female widows to act like this, unless defending egg sacks. Is this a sub species native to New Mexico, or some sort of infestation I was previously unaware of?
How you want your letter signed:  Alexa Rense

Black Widow

Dear Alexa,
According to BugGuide:  “The
Latrodectus genus breaks down taxonomically into approximately 31 recognized species, five (5) of which are found in the United States; four (4) species are native, one (1) species (L. geometricus) was introduced.”  According to BugGuide data, it is the Western Black Widow that is found in both Oregon and New Mexico.  While the bite of a Western Black Widow can be dangerous, they are not an aggressive species, though many female spiders will defend eggs and young.  We are lamenting the loss of native Western Black Widows in Los Angeles where they seem to have been entirely replaced in recent years by the invasive Brown Widow.

What's That Bug? does not endorse extermination