Narrowleaf Four O'Clock (Mirabilis linearis) is a member of the Four O'Clock family (Nyctaginaceae), and it has extremely narrow leaves that are quite unlike those of the other family members found here in the Tucson area.
I observed this pink-flowered wildflower above 4000 feet (1219 m) along the Catalina Highway, but Narrowleaf Four O'Clocks can also be found growing at a much lower elevation in Sabino Canyon.
Sabino Canyon, because of its mountain runoff, shade, elevated humidity, and unique topography, allows many plants normally found at higher, cooler, wetter elevations to survive. The several Narrowleaf Four O'Clocks that I observed in Sabino Canyon were a quite a ways up a vertical, rocky cliff, and I couldn't safely reach them to get a photograph.