Holmes, W.C., J.R. Singhurst, and J.N. Mink. 2011. Heuchera americana (Saxifragaceae) in Texas. Phytoneuron 2011-6: HEUCHERAAMERICANA (SAXIFRAGACEAE) IN TEXAS Walter C. Holmes Department of Biology Baylor University Waco, Texas 76798-7388 U.S.A. walter_holmes@baylor.edu Jason R. Singhurst Wildlife Diversity Program Texas Parks and Wildlife Department 3000 South IH-35, Suite 100 Austin, Texas 78704 U.S.A. jason.singhurst@tpwd.state.tx.us Jeffrey N Mink Department of Biology Baylor University Waco, Texas 76798-7388 U.S.A. jeffrey_minkj@bayior.edu ABSTRACT The occurrence and distribution of Heuchera americana in Texas are clarified and expanded with documentation for five counties: Bowie, Cass, Harrison, Red River, and San Augustine. A distribution map and photo of a specimen from Harrison County are included. KEY WORDS: Heuchera, Saxifragaceae, Texas, USA. The purpose of this paper is to clarify and document the known distribution of Heuchera americana L. (Saxifragraceae) in Texas. The initial mention of the species in the state appears to be by Correll and Johnston (1970), who cited the distribution as northeast Te?^as. Hatch et ai. (1990) cited the species as occurring in the Pineywoods, Post Oak Savannahs, and Biackland Prairies of the state, which was later referenced by Diggs et al. (1999) to include the species in their manual of the Illustrated Flora of North Central Texas. Johnston (1990) and Jones et al. (1997) also cited H. americana as occurring in the state. Turner et al. (2003) mapped the species as occurring in Bowie Co, Curiously; the PLANTS database (USDA NRCS 2011), Weils (1984), and Wells and Shipes (2009) do not mention the occurrence of H. americana in Texas. Although the species has frequently been cited as occurring in the state, we have not located a published record of a specimen citation for Texas. The following list of exsiccata documents the occurrence of Heuchera americana in five Texas counties: Bowie, Cass, Harrison, Red River, and San Augustine (Fig. 1). We are including all collections because of the rarity of the species in Texas herbaria. The Harrison Co. specimen (Correll & Lundell 18785, SMU), the oldest Texas collection of the species located, is shown in Fig. 2. Specimens cited: TEXAS. Bowie Co.: On wooded bluff along Rte. 559, 1 mile north of Wamba, 30 April 1969, Correll 37142 (LL); above waterworks Lake, just NE of Wamba, hardwood slopes, 13 Jul 1965, Correll 31281 (LL); Bringie Lake, a mesic white oak-chinquapin oak forest; fls cream, 15 April 2000, Holmes, Singhurst, & Baldridge 10831 (BAYLU TEX); Bringie Lake, 1.4 mi. NE of Wamba, Holmes, Singhurst, ; City of Texarkana property. 10 May 2000, Singhurst 8856 (BAYLU); north of Wamba; very steep, wooded slopes, May 1 978, Ajilvsgi ''340 (BRIT). Cass Co. : Nature Guided Trail, Atlanta State Park, 12 May 1999, Holmes & Singhurst 9998 (BAYLU). Harrison Co.: on rich wooded slope of ravine along Cypress Bayou, below small roadside park near Jefferson, 23 May 1958, Correll & Lundell 18785 (SMU). Red River Co.: Mrs. Joe Swindle's land, NE of Woodland Cemetery ca. 0.4 mi. near Woodland Community, headwater springs of 'lanyard Creek, Cretaceous Woodbine Formation outcrop at merger with lower Eagleford Shale, 1 April 2000, Singhurst & Swindle 7903 (BAYLU). St. Augustine Co.: Sabine National Forest, Compartment 65, Cypress Creek, calcareous seep slope forest on Weches outcrop, 24 April 2002, Singhurst 1 1 155 (BAYLU). The San Augustine station is approximately 240 km south of the only previously known records in Bowie Co. All of the Bowie Co. specimens are from the Bringle Lake area (a reservoir impounded in 1929) that has been heavily impacted by recent construction of a golf course and formation of Texas A&M University-Texarkana, with other development planned or in progress. Heuchera is considered to be a peripheral species in Texas, the distribution being continuous with that of Oklahoma, Arkansas, and Louisiana. It is of conservation concern (SI, with 6 or fewer populations, rare with in Texas). Within the state, the species occurs in hardwood forests growing on calcareous substrates subject to wet season seepage. Generally these forests are located at the base of slopes or on horizontal benches on slopes. Typical overstory trees include Quercus alba, Carya tomentosa (= Carya alba), Acer rubrum, Fraxinus americana, and Carpinus carolintana. Understory woody vegetation consists of Lindera benzoin, Itea virginica, Alnus serrulata, Viburnum rufidulum, and immature specimens of the overstory vegetation. Associated herbaceous vegetation includes Polystichum acrostichoides, Athyrium felix-femina subsp. asplenioides, Packera obovata, Carex spp., and Tipularia discolor. Correll and Johnston (1970) referred the Texas specimens of Heuchera americana to var. brevipetala Rosendahl, Butters, & Lakela, which was treated by Wells and Shipes (2009) as H. americana var. americana. All Texas specimens examined are referable to H. americana \sr. americana. ACKNOWLEDGEMENTS The authors are greatly indebted to Tiana Franklin of the Botanical Research Institute of Texas (BRIT) in Fort Worth for providing digital photographs of specimens of Heuchera americana. Information on H. americana specimens from TEX'LL was acquired from the Flora of Texas Database (http//www.biosci.utexas.edu/prc/Tex.htm/), Plant Resources Center, The University of Texas, Austin. '•..iiJI. US jihI \|i- I,.|inM..,i Foundation, Renner. Diggs, G.M., Jr., B.L. Lipscomb, and R.J. O'Kennon. 1999. Shinners and Mahler's Illustrated Flora of North Central Texas. Sida Bot. Misc. 16, Bot. Research Inst, of Texas, Fort Worth. Johnston, M.C. 1990. The Vascular Plants of Texas. A List, Updating the Manual of the Vascular Plants of Texas, 2 nd ed. Published by the author, Austin. Jones, S.D., J.K. Wipff, and P.M. Montgomery. 1997. Vascular plants of Texas. A Comprehensive Checklist Including Synonymy, Bibliography, and Index. Univ. of Texas Press, Austin. Hatch, S.L. K.N. Gandhi, and L.E.Brown. 1990. Checklist of the Vascular Plants of Texas. Texas Agricultural Experimental Station MP-1655, Texas A&M Univ.. College Station. cJmes, Snghust , and Mink Heuchera dm ericana in Texas 3 Turner, B.L., H. Nichols, Q Denny, and 0. Doron 2003. Atlas of the vascular plants of Texas. Si da Bot. Misc. 24 (2 vols.). Bot. Research Inst. Teas, Fort Worth. USDA.NRSC. 2011. The PLANTS Database (http://plants.usda.gDV, January 2011). National Data Center, Baton Rouge, Louisiana. Wells, E.F. 1984. A revision, of the genus Heuchera (Saxifragraceae) in. eastern North America. Syst Bot. Monogr 3: 45-121. Wells, E.F. andB.G. Snipes. 2009. Heuchera. Pp. 84-104 in Fiona of North America Editorial Committee, Flora of North America, Vol. 8, Magnoliophyta: Paeoniaceaeto Ericaceae Figure 1. Distribution of Heuchera armricana in Texas. The numbers are in counties in. which the species has been documented: 1. Red River, 2. B owie; 3. Cass; 4. Harrison; and 5. SanAugustin Holmes, Singhurst, and Mink: Heuchera americana in Texas 4 Figure 2. Correll &Lundett 18785 (SMU), from Harrison Co., Texas; the oldest Heuchera americana specimen from the state located during the study. Used with permission of BRIT Virtual Herbarium. Atrium Biodiversity Information System, Botanical Research Institute of Texas, http://atrium.brit.org. Accessed 11 Feb 2011.