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Archive for June 1, 2017

Arachnid Anomaly

6-1-17 wolf spider 124

Wolf spiders and nursery web spiders look a lot alike. One way to tell one from the other is to look at the arrangement of the spider’s eyes. Nursery web spiders (family Pisauridae) have two rows of four eyes each, all roughly the same size. Wolf spiders (family Lycosidae) have a row of four small eyes, above which there are two large eyes, with two very small eyes a short distance behind them. From looking at the eyes of the pictured spider, one would assume it was a wolf spider (smallest, topmost eyes are not visible).

However, a second way to distinguish these two families of spiders is to notice how the females carry their egg sacs (the females of both species carry their egg sacs with them wherever they go). Wolf spiders attach their egg sacs to the spinnerets located at the tip of their abdomen, whereas nursery web spiders carry them in their pedipalps (two appendages that look like, but aren’t, legs ) and mouthparts, as seen in this photo.

Thus, this particular spider has wolf spider eye arrangement, and practices a nursery web spider egg sac-carrying technique. My assumption is that this is a mixed up wolf spider or one with tired spinnerets.

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