Spider Explosion!

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Heavy rain (an understatement) during the last week has washed any remaining spiders off the foliage and the action is now all down in the leaf litter. It's been sift-and-sort all the way this week. I've examined leaf litter from four different sites and the number of Microneta viaria has exploded. I have found them as the predominant species at all the sites I have visited, and at one site, they are all I found! This has solved one mystery for me. For the past few months I have been finding immature specimens of a spider with a grey prosoma and orange opisthosoma I have not been able to identify:



It's now clear that these were immature Microneta viaria and now I can see why there were so many of them! Fortunately, they are easy to identify when mature. Both the male palps and female epigyne are characteristic and the prolateral spine on the inside of tibia1 is also helpful.




Epigyne

I think it's no accident that this has coincided with large numbers of springtails in the leaf litter (particularly Dicyrtomina saundersi) - food availability has spurred mass maturation.