Ozyptila praticola Catch-Up Post

Map 1. Sites sampled for Ozyptila praticola mid-August to 

mid-October, 2017.

The past two months have been a whirlwind. In addition to the usual collecting trips with Rod Crawford, I intensified my ongoing search for the introduced European crab spider Ozyptila praticola (Thomisidae). For the latter, I've tapped over 3,000 fallen conifer cones at 48 sampling sites (Map 1) since mid-August. I focused my search in areas that I suspected were on the periphery of or just beyond O. praticola's local range. I also re-sampled a few sites within its known range to confirm its presence with mature specimens where previously I'd collected only juveniles. Instead of blogging separately about each sampling day and site as I usually do, I'll summarize them together here.

Map 2. Ozyptila praticola confirmed during the mid-August
to mid-October, 2017, sampling period (blue pins)

I confirmed the presence of O. praticola at only three locations during this sampling period: Woodinville, Bainbridge Island and Mercer Island (Map 2). Only the Bainbridge Island sample represented an extension of the known range of the species.

Based on the data I've gathered to date (Map 3), the core range of O. praticola in Washington appears to be the urbanized western lowlands of King County and Snohomish County. In addition, there appears to be a small disjunct population in Bellingham (Whatcom County). The presence of O. praticola on Bainbridge Island signals the need for more sampling in Kitsap County, especially the Bremerton area. The search continues.

Map 3. Ozyptila praticola in Washington state.
Blue: O. praticola confirmed via adult specimen.
Yellow: Juvenile O. ?praticola found.
Red: No O. praticola adults or ?praticola juveniles found.
Purple: O. praticola confirmed in British Columbia, Canada by Bennett et al. (2017)