Pison electrum, a new species from Baltic amber characterized mainly by a notched mandible and second recurrent vein ending on a submarginal cell III, is not closely related to any of the extant species.
Antropov, Alexander V. and Pulawski, Wojciech J., "A New Species of Pison Jurine from. Baltic Amber (Hymenoptera: Sphecidae)" (1989). An. Paper 20.
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