Thanks to some sharp eyed grower colleagues - and well equipped with some impressive hand lens and field microscopes I might add - I got my hands on some good Lewis mites and was able get some pictures. Truly, these do look different than twospotted spider mite. Checked out with UCCE colleague Surendra Dara for confirmation and yes, we have our Lewis mite.
See photo below.
Attached Images:
Lewis mite from strawberry field in the vicinity of San Andreas Road. Note how spots run the length of the body and somewhat geometric appearance of the body. Also smaller when compared to twospotted mites.
UCCE stock photo twospotted spider mite.
My own photo, twospotted spider mite. Spots are restricted to shoulders and are large in comparison to body. Larger and rounder than Lewis mite.