See https://www.inaturalist.org/observations/218386975.
Compare with presumably bona fide Lomatium nudicaule a few feet away https://www.inaturalist.org/observations/219211540
Last photo shows several Lomatium nudicaule in foreground and this single plant in the background.
Taller, leaf larger and possibly thicker, flower from leaf axil well above ground, secondary umbel upswept (possibly only from different floral stage) and with fewer flowers, slightly earlier flowering.
There was at least one small area with many of these, probably Lomatium lithosolamans. I suspect that this species, like farinosum, quintuplex, and cuspidatum, is regionally "rare" but in just the right environment very abundant (confirmation for L. lithosolamans awaits sping 2025). Lomatium have apparently speciated extensively and some occupy very narrow niches (https://botanicgardens.uw.edu/wp-content/uploads/sites/7/2016/11/Darrach-2017_Lomatium-%E2%80%93-WA-Botanical-Symposium.pdf).
This observation was on extreme lithosol that supports few species, even Artemisia rigida is stunted or absent. I found Lomatium quintuplex, Poa secunda, Lewisia rediviva, Phemeranthus spinecens, and probably Idahoa scapigera fruits.
7 bractlets per umbellet, bractlets linear to lanceolate; plant acaulous; perennial