Our only known station for this plant is a post oak flat just south of Half Moon Pond about 10 miles southwest of Mt. Vernon, Posey County. It is frequent here over several acres. The report for Marion County is doubtless an error.
Perennial, 3-7 dm; lvs sessile, lanceolate to lance-ovate or narrowly deltoid, 5-11 cm, acute to slenderly acuminate, the base obtuse to rounded or truncate; cyme usually solitary, racemiform, peduncled, few-fld, elongating during anthesis; sep linear-attenuate; cor erect, 3-6 cm, scarlet outside, yellow inside; fr 5-8 mm; 2n=48. Moist woods and thickets; N.C. to s. Ind., s. Mo., and Okla., s. to Fla. and Tex. May, June. Contains a poisonous alkaloid.
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.