20-April-2018 Tacoma, Washington

Site location map. Markers indicate traps in which no Ozyptila
 (red) or juvenile Ozyptila (yellow) were found.

I've tapped a lot of fallen conifer cones in Tacoma in my search for the introduced crab spider Ozyptila praticola, but never in the city's north end. So I decided, back on April 1st, to deploy a set of cardboard live traps in shrubs in that part of the city. I returned on the 20th to see who had moved into them in the mean time.

The long and the short of it is that, while all traps contained spiders (clubionids were the most common), only one trap contained any Ozyptila. The trap, wedged into a low fork in an Arbutus unedo shrub growing on the campus of University of Puget Sound, contained two juvenile Ozyptila that looked like praticola.

Not wanting to go home without being able to confirm which Ozyptila species I had found, I proceeded to tap a set of 50 Pseudotsuga menziesii cones which had fallen near the Arbutus. No luck! Next, I sifted two full bags of leaf & needle litter. Frustratingly, that exercise only turned up more juvenile O. ?praticola. Well, at least I know where to resume my search next time I'm in north Tacoma. I placed a new trap in the Arbutus and called it a day. If this does turn out to be O. praticola, it would appear to be a highly localized population.

Tacoma-area fallen cone (pins) and live trap (circles) samples.
Blue -- Ozyptila praticola confirmed with adult specimen
Yellow -- Ozyptila?praticola juveniles found
Red -- No Ozyptila found