This is the former (or current) "Acacia constricta var. vernicosa" which has fewer pinnae per leaf than A. constricta. USDA PLANTS and ITIS put this taxon in Vachellia and elevate it to species level, while The Plant List retains it as a subspecies of A. constricta.
http://plants.usda.gov/core/profile?symbol=VAVE
http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=819942
http://www.theplantlist.org/tpl1.1/record/tro-50294155