Eryngium longifolium Cav.

Eryngium longifolium Cav. Anal. Hist. Nat. 2: 133. 1800
Eryngium Watsoni Coult. & Rose; Rose, Contr. U. S. Nat. Herb. 8: 334. 1905. Eryngium Langlassei H. Wolff, Repert. Sp. Nov. 9: 417. 1911.
Slender, caulescent perennials, 5-20 dm. high, from a short, oblique, tuberous rootstock bearing a fascicle of fibrous-fleshy roots, the stems solitary, erect, branching; basal leaves numerous, broadly linear, 3-7 dm. long, 1-2 cm. broad, broadest at the base, attenuate at the apex, weakly spinose-ciliate, the spines slender, ascending, the longest 2-6 mm. long, axillary spines minute or wanting, the venation parallel; sheaths broader than the blades, vaginate, 6-12 cm. long; cauline leaves few, like the basal, amplexicaul, alternate, ascending, the upper greatly reduced, opposite; inflorescence divaricately cymose, the heads rather large, numerous, pedunculate, the flowers numerous; heads globose-ovoid to ovoid-cylindric, S— 15 mm. long, 8-10 mm. broad, rounded at apex and base; bracts 6-8, rigid, spreading to loosely reflexed, linear-lanceolate, 3-12 mm. long, I mm. broad, pungent, entire, much shorter than the heads; bractlets narrowly lanceolate, 3-5 mm. long, pungent, entire, occasionally puberulent (?), slightly exceeding the fruit; coma wanting; sepals broadly ovate, 1 mm. long, obtuse, apiculate; petals oval, about 1 mm. long; styles slender, exceeding the sepals; fruit turbinate, 2-3 mm. long, the calycine and lateral scales lanceolate, up to 1 mm. long, the dorsal greatly reduced or obsolete.
Type locality: Between Pachuco and Real del Monte, Hidalgo, collector unknown. Distribution: Jalisco to Mexico and Guerrero (Mexia 9028, Pringle 6197).

Eryngium longifolium là một loài thực vật có hoa trong họ Hoa tán. Loài này được Cav. mô tả khoa học đầu tiên năm 1800.