Subject: Unidentified, Unusual Egg Case
Location: Southern Michigan
April 27, 2013 7:39 pm
I found this unusual looking egg case, while hunting for fossils. It was in a crumbly, sedimentary boulder, along with dozens of sow bugs, which were exposed when I split the rock open. The eggs are visible as round bumps through the papery/silky covering. Was wondering if some type of spider made this, or another kind of arthropod such as the sow bugs?
Signature: Chris O
We do not recognize this thing, but we would not rule out a fungus. We are posting this as unidentified and we hope that either we or our readership might find and answer for you.
Dear Daniel: After looking all over the internet for similar photos & an answer, I found a link on Bug Guide which has an almost identical photo of this type of egg sac. It appears to be the creation of a type of ground spider. Species mentioned during my searching are gnaphosid, zelotes and corrinidae. Here’s a link to the pic on Bug Guide: http://bugguide.net/node/view/181688/bgpage
Thanks so much for following up on this posting.