MULTIPLE COMPLEMENTARY STUDIES CLARIFY WHICH CO-OCCURRING CONGENER PRESENTS THE GREATEST HYBRIDIZATION THREAT TO A RARE TEXAS ENDEMIC WILDFLOWER (HIBISCUS DASYCALYX: MALVACEAE) Melody P. Sain1*, Julia Norrell-Tober*, Katherine Barthel, Megan Seawright, Alyssa Blanton, Kate L. Hertweck2, John S. Placyk, Jr.3 Department of Biology and Center for Environment, Biodiversity, and Conservation University of Texas at Tyler 3900 University Blvd., Tyler, Texas 75799, U.S.A. Randall Small Department of Ecology & Evolutionary Biology University of Tennessee-Knoxville Dabney Hall, 1416 Circle Dr., Knoxville, Tennessee 37996, U.S.A.
[email protected] Lance R. Williams, Marsha G. Williams, Joshua A. Banta Department of Biology and Center for Environment, Biodiversity, and Conservation University of Texas at Tyler 3900 University Blvd., Tyler, Texas 75799, U.S.A.
[email protected],
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[email protected] *The two authors contributed equally to this work. 1Current address: Department of Botany, University of Wisconsin, Madison, Madison, Wisconsin 53706, U.S.A.,
[email protected] 2Current address: Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N, Seattle, Washington 98109, U.S.A.,
[email protected] 3Current address: Trinity Valley Community College, 100 Cardinal Dr., Athens, Texas 75751, U.S.A.,
[email protected] ABSTRACT The Neches River Rose Mallow (Hibiscus dasycalyx) is a rare wildflower endemic to Texas that is federally protected in the U.S.A. While previous work suggests that H. dasycalyx may be hybridizing with its widespread congeners, the Halberd-leaved Rose Mallow (H. laevis) and the Woolly Rose Mallow (H. moscheutos), this has not been studied in detail. We evaluated the relative threats to H.