1) Subspecies sayi always has some black maculation on the pronotum...varying from two distinct small and somewhat oblique spots, to larger spots which can become confluent, forming an inverted-"v" shape. The other two subspecies have pronotum entirely red, with no black on the pronotum. 2) Subspecies blandi differs from discoideus in its: smaller size; more narrow form; more sparse punctation (especially the pronotum); and more rounded apex (the apex of discoideus is described as "feebly truncate").
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