SV_UAIC-1139105
All these nymphs are 5 mm long, but their legs length and general coloration differ dramatically. I wondered if this was due to sex differences or to having captured the first and second instars. First, I suspected that they were all in their first instar because the second instar is documented to be 10.7 mm long on average, but a blog post by Margarethe Brummenrmann has a plate titled Development of the Giant Mesquite Bug that makes it obvious that these two nymphs are in their first and second instar respectively. In this series, the first instar is labeled as "Nymph 1" and the second instar as "Nymph 2"
Found on hopbush (Dodonaea viscosa) under a stand of mesquite trees
Coordinates: 31.335552, -110.937988
Elevation: 3,931 ft
Greater resolution image here