The gender call is based on observations of hundreds of individuals and dozens of “in copula” pairs at this site over the course of several seasons. In this population (now extirpated) sexually active females tend to be yellow rather than orange (not always); they have clear, fully formed spots on the elytra; they also have a butterfly pattern on the pronotum. Males often have undeveloped spots and a pattern suggestive of a panda face. These features are variable and admittedly not highly diagnostic, but another seems to always apply, and that is size: the bottom half of a mating pair is always larger than the top half; thus, females are larger, maybe not universally, but within this population.

While I did not see this individual mating, I did note that it had all the above characteristics including the larger size. In my mind there was little doubt at the time that it was a female, but this is not scientifically rigorous. I will leave it as “gender unknown” (but I still think it’s a female).

No doubt in my mind now, either - and I've always seen smaller males mating with much larger females, too, never the other way around. There are presumably exceptions that prove the rule, but I've never seen one myself.