The base color of
Z. luridus is apple green, and markings on the back may be very dark or rather light. The legs sometimes have dark or red bands on the distal ends of the femurs, but these can often be so light as to be almost invisible. When I've seen mating pairs, the males tend to be the darker ones, with the more pronounced red leg bands.
The best feature for recognition is the pair of delicate spines on the rear corners of the pronotum, which are rather long on the light colored individuals and shorter on the dark.
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