Latrodectus mactans (Southern Black Widow) and Latrodectus geometricus (Brown Widow)

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287

satanslilhelper

Arachnodemon
Old Timer
Joined
May 24, 2009
Messages
734
That 1st pic of the "mactans" looks like the widow has some color on its back. Is that just the lighting or does it have some orange spots on its abdomen? If so then it looks like a L. variolus which is the Northern widow.
Please correct me if I'm wrong.
 

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287
Here is a better picture (below).. Yes, she has markings on her back but we believe this is because she is a juviie. "From what I have read L.mactans generally has the hourglass as one whole marking while L.hesperus generally has it seperated into two triangles as in my pics." (Quote from an Arachnoboard Administrator)

The thread where we found most of our information is at the top of the page under "True Spiders and Other Arachnids"..

At first, we also thought she was a Northern Black Widow but after doing research, it seems as if she is a L. mactan.. we are not familiar with this species esp. in Florida because we're from Illinois so we might be wrong.. who knows! I am sure someone will correct me if I am wrong with the ID.

Picture; http://i68.photobucket.com/albums/i11/kelseyjane10/Creatures129.jpg
 

satanslilhelper

Arachnodemon
Old Timer
Joined
May 24, 2009
Messages
734
Here is a better picture (below).. Yes, she has markings on her back but we believe this is because she is a juviie. "From what I have read L.mactans generally has the hourglass as one whole marking while L.hesperus generally has it seperated into two triangles as in my pics." (Quote from an Arachnoboard Administrator)

The thread where we found most of our information is at the top of the page under "True Spiders and Other Arachnids"..

At first, we also thought she was a Northern Black Widow but after doing research, it seems as if she is a L. mactan.. we are not familiar with this species esp. in Florida because we're from Illinois so we might be wrong.. who knows! I am sure someone will correct me if I am wrong with the ID.

Picture; http://i68.photobucket.com/albums/i11/kelseyjane10/Creatures129.jpg
I found a bunch of these at work here in B'ham, AL and everyone ID'ed them as L. variolus.

 

satanslilhelper

Arachnodemon
Old Timer
Joined
May 24, 2009
Messages
734
I just checked on my recently molted girl and it has a different pattern than the previous pic. So, who knows you might be right.:? I guess I'll know after another molt for sure. Maybe they do change. I'll be happy either way. I love these little guys.:cool:
 

cacoseraph

ArachnoGod
Old Timer
Joined
Jan 5, 2005
Messages
8,328
i see tons of full glass heserpus


what is the size on the non brown one? she still has leg striping so i am guessing pretty little?
 

Widowman10

Arachno WIDOW
Old Timer
Joined
Jan 25, 2007
Messages
4,212
you are correct OP. it is a mactans.

beautiful widows!!
 

Widowman10

Arachno WIDOW
Old Timer
Joined
Jan 25, 2007
Messages
4,212
That 1st pic of the "mactans" looks like the widow has some color on its back. Is that just the lighting or does it have some orange spots on its abdomen? If so then it looks like a L. variolus which is the Northern widow.
Please correct me if I'm wrong.
the southeastern macs tend to have a lot more color than their darker relatives in other places. but macs most certainly have crazy color like the one in the pics.

I just checked on my recently molted girl and it has a different pattern than the previous pic. So, who knows you might be right.:? I guess I'll know after another molt for sure. Maybe they do change. I'll be happy either way. I love these little guys.:cool:
the closer she gets to maturity, the more you'll be able to tell.

i see tons of full glass heserpus
what is the size on the non brown one? she still has leg striping so i am guessing pretty little?
with macs, yes. but variolus will have annuli visible on the legs up until almost the ultimate molt. it's weird seeing a normally full-size widow with faint leg striping. but then she molts to the ultimate stage and they are gone.

hmm, i had more thoughts but i can't remember what i was going to ramble on about. i'll add later if needed.



edit: SLH, do you have a ventral shot of that girl?
 

Venom

Arachnoprince
Old Timer
Joined
Jul 21, 2002
Messages
1,709
Definitely a mactans. Hesperus tends to have a maroon-ish tint to the abdomen, and both variolus and hesperus have different hourglasses than the mactans.

There are no hesperus or variolus in central Florida anyway, as variolus only makes it into the northern fringe of Florida. ;)
 

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287
Wowzaa, these beauties sure are confusing to ID esp. when the female's markings change with age. The L. mactan pictured in this thread is very small in size.. MAYBE the size of a dime (including leg span).

Widowman10; what species of these spidiies are in the state of Florida? As far as the internet tells me; Latrodectus bishopi, Latrodectus geometricus, Latrodectus mactans, and Latrodectus variolus.. is this correct?? is that ALL the widow species? Spill that brain of yours mistaa.. and thanks, we plan on keeping them for a few months to watch and learn as much as possible about this beautiful species! =)

THANKS EVERYONE.. we appreciate all the thoughts and help with making sure this was a correct ID for both spiders!
 

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287
Definitely a mactans. Hesperus tends to have a maroon-ish tint to the abdomen, and both variolus and hesperus have different hourglasses than the mactans.

There are no hesperus or variolus in central Florida anyway, as variolus only makes it into the northern fringe of Florida. ;)
Ahh, thank you for posting this because I didn't think the L. hesperus was in my area either but like I said before, we are new to this species and Florida! What pretty little ladies, none the less. :)
 

Widowman10

Arachno WIDOW
Old Timer
Joined
Jan 25, 2007
Messages
4,212
thanks! about what size is she? i would venture to say based on those pictures that you have a mactans.
 

satanslilhelper

Arachnodemon
Old Timer
Joined
May 24, 2009
Messages
734
She's a scrunched up 3/4 in.. So, I would say she's probably closer to an inch to an inch and 1/4. She now has a red band on her abdomen compared to the funky coloration she had before she molted. I'm excited that this is a mactans.
 

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287
She's a scrunched up 3/4 in.. So, I would say she's probably closer to an inch to an inch and 1/4. She now has a red band on her abdomen compared to the funky coloration she had before she molted. I'm excited that this is a mactans.
Just curious; what makes the L. mactans so neat?? Is there something about them that is different than the other species?? I think the one we have is just beautiful but I didn't know if they were rare or had certain special markings.. ? (besides the hour glass, of course!)
 

satanslilhelper

Arachnodemon
Old Timer
Joined
May 24, 2009
Messages
734
For me it's the fact that I've lived in Alabama all of my 29 years and I've never found one on my own until now. I saw one at the Natural History Museum when I was in elementary school. My boss at work even brought me one earlier this summer, but he crushed some of its legs and it died later that night.

I must say that until this last spring I've never actively pursued finding one. After raising T's for several years now I wanted to branch out and find one. I think they have an elegant beauty to them.
 

davisfam

Arachnoknight
Joined
Jul 19, 2010
Messages
287
L. mactans molted tonight!! =)

The little gal molted tonight and has grown in size, of course. Also, her markings on her back have changed a bit. She is now around the size of a nickle, if not a little bigger; including leg span. Here is a couple pictures we took of her tonight. Enjoy!! ;)



 
Top