Lvs usually oblong or obovate- oblong, often twice as long as wide, cal-lobes hirsutulous at the tip, otherwise glabrous; cor conic in bud, gradually acute to acuminate, scarcely twisted, at anthesis brownish-purple to greenish-purple, its lobes narrowly lanceolate, 8-14 mm, thrice as long as the cal; corona nearly rotate, much shorter than the gynostegium; pollen-sacs inconspicuous, with narrow slits, the pollinia ±pendulous; fr glabrous, 8-13 mm, sharply angled but not winged. Moist woods and thickets; se. Va. to Fla. and Tex., and up the Mississippi embayment to s. Mo. and s. Ind. July. (Gonolobus g.; Vincetoxicum g.)

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

©The New York Botanical Garden. All rights reserved. Used by permission.

From Flora of Indiana (1940) by Charles C. Deam

Climbing vines in low woodland and in cultivated fields.

...... 

Indiana Coefficient of Conservatism: C = 7 

Wetland Indicator Status: FACW

Diagnostic Traits: hirsute vines; leaves opposite, narrowly ovate, bases cordate, short acuminate; flower crowns low, 10-lobed, at base of anther-column; flowers purple-brown, corolla lobes broadly lanceolate, 2× or more as long as calyx-lobes; follicle fruits costate-angled.