Description: Biennial or perennial herb, 1 - 2 m (3.3 - 6.6 ft) tall. Stems striated, erect, and glabrous (without hair). Basal leaves spiny, to 29 cm (11.4 in.) long, crowded into whorls and sparsely hairy; stem leaves alternate and sessile. Inflorescence a discoid head, subtended by spiny bracts 2 - 3.5 cm (0.8 - 1.4 in.) long; ray florets absent, disk florets pale, rosy purple. Fruit an achene, 6.5 mm (0.26in.) long, with whitish pappus bristles. Time of flowering: July to August.
Habitat: Known to occur in alpine, bristlecone pine, and mixed conifer
communities, on gravelly slopes, dry ridges, avalanche chutes, scree slopes, and around springs. Elevations: 2,774 - 3,350 m (9,100 - 11,000 ft).
Range: Endemic to the Spring Mountains, Clark County, Nevada. Found in Deer Creek, Lee Canyon, Kyle Canyon, and on high elevation ridges from Griffith Peak to Mummy Mountain.
Comments: Distinguished from other thistles in the Spring Mountains by the long spines equaling or surpassing flower heads. Said to be one of the most heavily armed thistles.