Hecastocleis is a monotypic genus of plants in the daisy family containing the single species Hecastocleis shockleyi, which is known by the common name prickleleaf. This plant is native to the desert mountains and plains of eastern California and western Nevada, where it grows on arid, rocky slopes and flats. This is a low, brambly shrub producing a tangle of stiff, branching stems reaching heights between 40 and 70 centimeters. The stems have sparse glandular hairs and are lined with small pointed green leaves with a row of widely-spaced spines along each edge. As the leaf dries and its flesh falls away, the spines remain as hard prickles. At the end of stem branches are solitary flower heads, each enclosed between flat, oval-shaped, sharply toothed, leaflike, pale yellow bracts. Between the bracts are the flower parts, which are pinkish when new and open into a greenish-yellow corolla. The fruit is a cylindrical achene. Classification Hecastocleis shockleyi is the only species in the subfamily Hecastocleidoideae of the aster family (Asteraceae). Botanists at least as early as Asa Gray (in 1882) remarked on its distinctiveness; it appears to have no close relatives within the aster family.[1][2] References 1. ^ Panero, JL; VA Funk (2002-12-30). "Toward a phylogenetic subfamilial classification for the Compositae (Asteraceae)" (PDF). Proceedings of the Biological Society of Washington (Biological Society of Washington) 115 (4): 909–922. http://www.mnh.si.edu/biodiversity/bdg/Panero&Funk2002.pdf. Retrieved on 12 June 2008. External links
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