Eratigena

Picture ID 76745

Submitted by:
eightleg
Submitted: Aug 9, 2019
Photographed: Aug 9, 2019
Spider: Eratigena
Location: Oregon, United States
Spotted Outdoors: Man-made structure (building wall, fences, etc.)
Found in web?: No
Attributes: Dorsal

7 Comments

oldest

newest most voted

Inline Feedbacks

View all comments

Eightleg

Photo Owner

August 9, 2019 5:11 pm

Found this brown Spider in my garage and was really curious about what kind it was. It moves really fast and stops when it is blocked by a brightly colored object.

ItsyBitsy

Moderator

August 9, 2019 5:36 pm

Giant House Spider, Eratigena duellica or saeva.

j_staff99

Reply to ItsyBitsy

November 18, 2019 11:45 am

Is saeva still in use?

ItsyBitsy

Moderator

Reply to j_staff99

November 18, 2019 7:43 pm

Yes, what happened is duellica, saeva, and atrica were synonimized in 2013 … then DNA analysis was done showing them to be three distinct species after all (see “Oxford & Bolzern, 2018). It was also shown that in some places there is potential for hybridization between saeva and duellica, sometimes I leave them at genus for this reason.
https://wsc.nmbe.ch/species/46142/Eratigena_saeva

j_staff99

Reply to ItsyBitsy

November 19, 2019 6:22 pm

Oh that’s interesting! So is genetics the only known way to distinguish them?

ItsyBitsy

Moderator

Reply to j_staff99

November 19, 2019 8:30 pm

There are morphological differences. I can make an educated guess based on location and subtle differences in the patterns. I have an idea how to distinguish saeva from duellica but it’s based on only one I saw IDed as saeva on the British Arachnological Society site, I don’t know if it’s reliable… so if I see that variation in areas where the species might overlap I’m inclined to file those to genus rather than to species … atrica is a little easier to distinguish … close examination of the genitalia can differentiate them with more certainty.