Hooked s. Low and often spreading, to 4 dm, branched from the base or only above; rays 5-14, ascending or suberect, unequal, to 1.5 cm; pedicels 2-6, to 7 mm, the central umbellets 1-fld, sessile; fr 1.5-2 mm, covered with short uncinate bristles; 2n=16. Dry prairies and barrens, and a weed in waste places; Ariz. and n. Mex. to Okla., La., Mo., and w. Ky., and rarely intr. e. to N.Y. May, June.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Wiggins 1964, Martin and Hutchins 1980, Baldwin et al 2015, Kearny and Peebles 1979, Felger et al 2014
Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Low, spreading annual herb from a taproot; stems alternately branching, glabrous, 5-40 cm. Leaves: Alternate, cauline, ternately decompound (divided into 3 segments, and then each segment is again divided into 3 segments), blade 7-25 mm wide, ovate in outline; ultimate segments 2-18 mm, thread-like; petiole 3-20 mm. Flowers: White, in axillary and terminal compound umbels, on peduncles 1-5 cm, exceeding the leaves; umbels lacking bracts, secondary umbels with few bractlets, thread-like to linear, entire or toothed; rays 5-14, 1-15 mm, generally ascending, very unequal; flowers on pedicels generally less than 7 mm. Fruits: Capsule splitting into 2 single seeded mericarps, widely ovate, 1.5-2 mm wide, with prominent ribs and short bristles with hooked tips. Ecology: Found on rocky slopes and sandy flats from 1,000-5,000 ft (305-1524 m); flowers February-May. Distribution: Most of southern US, from CA east to NC; south to n MEX. Notes: Identify this white flowered member of the carrot family by its sparse, open, nearly bractless umbels; delicate leaves divided into threadlike segments; and seeds with hooked bristles. Nesom (2012) segregated western individuals (west of Texas) of this species into a new species and is calling them Spermolepis laterifolia. Appears similar to Yabea microcarpa, but that species has larger fruits, >5mm long, and the stems and leaves are pubescent with hispid hairs. Daucus pusillus is also hairy, has fruits with barbed (rather than hooked) bristles, and the umbels usually have long leafy bracts. Ethnobotany: None. At least one species in this genus is reported as poisonous. Etymology: Spermolepis is from Greek sperma, seed and lepis, scale, for scale seeded; echinata means covered with prickles like a hedgehog. Synonyms: Apium echinatum Editor: SBuckley 2010, FSCoburn 2015, AHazelton 2015