Fort Ord Button Celery is just beginning to flower in the receding vernal pools in Mary’s Valley in Fort Ord National Monument. Link to observation last June showing closer view of the flowers: https://www.inaturalist.org/observations/168778807

Fort Ord Button-Celery (Eryngium montereyense) Endemic to coastal vernal pools on Fort Ord.
Conservation Status: Endangered. 1B.1 in California, US (CNPS)
California Native Plant Society, California Rare Plant Rank 1B.1: Plants Rare, Threatened, or Endangered in California and Elsewhere - Seriously threatened in California.

Jepson eFlora: Native. "Glabrous. Stem: branches decumbent, 10--15 cm, slender. Leaf: basal <= 16 cm, linear, pinnate with short linear to lanceolate lobes or entire, cauline <= 5 cm, coarsely serrated. Inflorescence: heads 9--12 mm; peduncle 10--15 mm; bracts linear, 5--9 mm, 1.5--2.5 mm wide, spines 0. Flower: sepals 2 mm, lance-ovate, entire; petals 0.5--1 mm, oblanceolate, white; styles <= sepals. Fruit: 1.5--3 mm, obconic; scales unequal, proximal conical, distal lance-attenuate.
Ecology: Vernal pools, seasonally wet swales; Elevation: 140 m. Bioregional Distribution: CCo (in Monterey Co.). Flowering Time: May--July"

Jepson eFlora https://ucjeps.berkeley.edu/eflora/eflora_display.php?tid=93913

Calflora (sightings in Monterey County) https://www.calflora.org/entry/observ.html?track=m#srch=t&lpcli=t&taxon=Eryngium+montereyense&chk=t&cch=t&cnabh=t&inat=r&cc=MNT

Flora of Fort Ord: Monterey County, California, David Styer, 2019 (species discovered on Fort Ord after 2019 (1st edition) publication date) Location of Mary's Valley, p. 1
"Dean Taylor has noted the very prostrate form of Ft. Ord's E. armatum, and wonders if more study might reveal that more than one taxon is represented."
Flora of Fort Ord: Monterey County, California, David Styer, 2019, p. 23.

"Newly described species endemic to FONM vernal pools and moist wetland swales" (10/2022) at: https://www.phytoneuron.net/wp-content/uploads/2022/10/45PhytoN-Eryngiummontereyense.pdf (1.3 MB pdf is downloadable)
ABSTRACT: Eryngium montereyense is "described from the Monterey Bay region of central coastal California. The new button-celery occurs in vernal pools at Fort Ord National Monument, which until recently was inaccessible for botanical survey. The new taxon differs from the parapatric E. armatum of coastal prairie in its smaller size, prostrate habit, lobed linear leaves, and vernal pool habitat."