I was taking photos of small 10 mm bee flies when this large species landed. The area was predominantly grass bordered by trees except for a few bare patches. This individual kept flying short distances then returning to perch on the ground.The wing pattern suggests Exoprosopa dorcadion to me but I don't understand the technical explanation to differentiate between similar species so I'm putting this on the genus page. There are no examples of this species in the guide for my region but the range is supposed to be NB - BC in Canada so it should be found here. Your help is much appreciated. Thanks.