Duration: Perennial

Nativity: Native

Lifeform: Forb/Herb

General: Herbaceous perennials from a cylindric taproot; stems stout, erect, simple to branching, somewhat striated; herbage glabrous, light grayish green to silvery in color.

Leaves: Basal rosette and alternate cauline leaves; lower cauline leaves pinnatifid to bipinnatisect; basal leaves pinnatisect to spinose-serrate.

Flowers: Small, whitish, clustered in dense bracteate heads which are in turn arranged in open, long-peduncled panicles. Bracts subtending the heads are yellowish above, lanceolate to linear-lanceolate, 12-25 mm long, entire or with 1-2 pairs of lateral spines near the middle; floral bractlets subtending each small flower are usually entire; calyx lobes lanceolate to ovate, obtuse or acute; corollas white or bluish white.

Fruits: Capsule splitting into 2 single seeded mericarps, ovoid, flattened laterally, covered with hyaline scales or tubercules, the ribs obsolete, with several inconspicuous oil tubes. Seed faces flat.

Ecology: Found on plains and along water courses, from 4,000-6,500 ft (1219-1981 m); flowering August-October.

Distribution: se AZ, s NM, w TX, south to n MEX.

Notes: The dense ovoid heads of flowers, superficially resembling Ranunculaceae, along with the prominent, spiky-looking, lateral, subtending bracts make this species stand out. A good indicator for this species are the pinnatifid to bipinnatisect stem leaves that lack spines (if stem leaves spinose-serrate, the species is likely E. lemmoni).

Ethnobotany: There is no use recorded for this species, but other species in this genus have uses.

Etymology: Eryngium is derived from the Greek word erungos for thistle, alluding to the spiny leaves that characterize this genus; heterophyllum means means that the leaves are different on the same plant.

Synonyms: Eryngium altamiranoi, Eryngium confusum, Eryngium endlichii, Eryngium medium, Eryngium wrightii

Editor: LCrumbacher 2012, AHazelton 2015