Euphorbia strictospora Engelm.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
Species Description - A chiefly sw. sp. with virtually entire styles, and with mottled, punctate-pitted seeds depressed-punctate at base and sharply acute at the tip, barely encroaches into our range in w. Io.