This comparative image comprises specimens collected at two sites within about a mile of each other in east central MN between May 27 and August 9 across several years. The largest three I trust are plectilis (WS 24, 24, 21 from top). The right column is less clear. The most conservative interpretation being that they are all tertialis, the topmost being unusually small (WS 16.5, 17, 18.5 from top). Alternatively, the bottom two might be small plectilis and the top one a small tertialis. Or, least likely, the bottom two might be tertialis and the top one tennesseensis (presently recorded only from TN). Clearly dissection would be needed to confirm species IDs for all but the largest specimens. The 'missing' abdomen has been retained but not dissected.
Perhaps of interest, of eight specimens (two not shown) three of four smaller individuals were taken in mixed upland woods while all four larger ones were taken from the edge of a swamp. The dates for smaller and larger specimens overlap entirely (though the three largest were all from early August). Since the sample size is small these observations may be trivial.
TL: 8-8-18 (swamp); ML: 8-5-18 (swamp); BL: 8-5-18 (swamp); TR: 5-27-15 (upland); MR: 8-9-19 (upland); BR: 6-8-18 (swamp).