Figure 2: Representative Bombus impatiens forewing and proboscis scanned at 2400dpi and portion of an antenna’s nail polish cast.

(a) Right forewing and (b) proboscis. White arrows indicate start and end points for length measures made in ImageJ. (c) Nail polish cast of the 7th antennal segment showing the boundary between the zone with pore plates (bottom) and the zone with only hair plates (top). White arrows indicate several pore plates at the boundary.