In past Fall seasons, I have serendipitously encountered a few specimens of this beautiful species, Megacyllene robusta Linsley & Chemsak:
Linsley and Chemsak
From my field notes of prior specimens (3), M. robusta adults were collected in late morning to early afternoon in late October. One locality, where three were found, is a service station surrounded by Mesquite/Grassland at 4166 feet elevation. One beetle was found on a sunny white wall and two others around the gas pump islands. Anecdotally, other species of Cerambycidae are known to be attracted to petroleum distillates. One that immediately comes to mind is the Banded Alder Borer, Rosalia funebris Motschulsky, which is commonly attracted to volatiles of freshly painted buildings and creosote-treated utility poles. Agreed, my inference that M. robusta may be similarly attracted is pure speculation.
In southeast Arizona, there are two other temporally and geographically sympatric species: M. antennata (White), and M. snowi snowi (Casey).
For my efforts, I follow recipes and deployment tips suggested by colleagues, Missouri entomologist, Ted MacRae, author of the highly recommended Beetles in the Bush, and Cerambycid cognescenti, Fred Skillman, Longhorn Ranch, Dragoon Mountains, Arizona ...
Bring 12 oz. dark molasses or 1 lb. brown sugar and 12 oz. beer, wine, or similar libation up to 1 gal. with water. Add a packet of active dry baker’s yeast to get the fermentation process started and mix well.
For best results, hang the trap in a tree or suitable shrub along the edge of forest borders. Traps placed inside forests or stands of vegetation usually yield smaller amounts of beetles but possibly different species.
Add 1-quart of fresh liquid. Generally, it will take 2-3 days for the liquid to start fermenting and become attractive. It will remain so for about another week.
Check traps every 2-3 days by pouring the liquid bait through a fine kitchen strainer into another container. Reuse or replace the liquid as necessary. A can of beer or other alcoholic beverage can be used to replenish the liquid to a suitable level.
Collected specimens should be washed in water to remove bait residue.
Here then, are my trap localities in the Sulphur Springs Valley, Cochise County ...
Below. Locality 2. Upper Sonoran mesquite/grassland at 4185 feet elevation. The area is being utilized as open range. Three traps were placed here among many large stands of old growth mesquite.