Pincushions (Chaenactis spp.)
The flower above was photographed in lower Hot Springs Canyon on March 6, 2008. Six species of Chaenactis are known in Arizona. Epple (1995, pp. 264-5) describes two of them, and we will tentatively distinguish them as evident here, based on leaf differences. The flower above, and the plants directly below (flowering on March 27, 2004 in Hot Springs Canyon) appear to fit the leaf pattern of "Esteve's Pincushion" (Chaenactic stevioides) in having "grayish green, woolly [leaves], divided twice into many short, thick, very narrow segments":
In contrast, this stand of pincushions below, photographed on March 28, 2004 in another location of the same area, displays leaves that fit Epple's criterion of "Green [leaves], divided into linear lobes; to 3" long": (click on the image for a clearer close-up)
The differences appear to be clear here. This cluster photographed in April 2005 on a terrace overlooking lower Hot Springs Canyon has leaves looking like the Esteve's species, but also shows some pinkish coloration.
Below left, flower photographed in lower Sierra Blanca Canyon in March 2005 (complete with insect visitor!); below right, one photographed in lower Hot Springs Canyon on March 06, 2008. (Click on each image to enlarge it.)..