Note that in convergens, the apical region of each elytron bears three large, prominent spots, whereas at least two of these are fused in glacialis. Also, glacialis lacks the pair of smaller spots along the inner elytral margin, while the humeral spot (visible in my image as a small smudge on the right elytron) is smaller and much less defined.
The pronotal pattern of convergens is dash-like, whereas in glacialis it has more of a violin f-hole shape. glacialis also seems to be somewhat lighter in color (although my old specimen of this species is red like a conver*gens; I think that's probably just the result of fading.)
Both species are probably quite variable, but I think this case presents us with a good glacialis candidate. A fine comparison image of glacialis can be found in this poster.

you got it, but using Gordon (1), I concur with H. glacialis

to my ignorant question. Now I know. Thanks, Stephen.

I often ask stupid questions, as you might notice from time to time :-) But hey, we're all here to learn, aren't we?