Journal archives for August 2021

August 09, 2021

August Agelenopsis

9 August 2021

Tis the season for Agelenopsis, the grass spiders. As their name implies, they are often found in grassy habitats where they make a sheet-like web with a funnel-like retreat in which the spider hides. The web itself is not sticky like it is in orbweavers. The spider waits in its retreat for a prey item to land on the sheet. The slightest vibration of the sheet acts like a starting gun at a track meet and the spider rushes out to try and grab the prey. You can see this behavior by taking a grass blade and just lightly touch the web of one of these spiders.

Grass spiders may just as well be named the gutter spiders or the siding spiders. I often find their webs behind the downspout on the corner of my house or extending outward from a 90-degree corner, their retreat tucked back into the edge of the siding. My front porch has several Agelenopsis webs because the spiders are taking advantage of the abundant insect prey that are attracted to the porch light.

Minnesota has records of seven species of grass spiders and they all look very much alike. The most common species (from my experience) is Agelenopsis potteri or Potter's Grass Spider. Distinguishing between the different species is very difficult (particularly in the females) and dissection of the genitalia is often required (and even then it can be tricky). Most my IDs are left at genus.

More information on this genus can be found on BugGuide here: https://bugguide.net/node/view/2001.

Posted on August 09, 2021 15:14 by cheins1 cheins1 | 4 comments | Leave a comment