Studies in the vascular flora of the southeastern United States. VIII

Abstract

As pari of ongoing efforts to understand, document, and conserve the flora of the southeastern United States, we make new combinations to accord with our generic taxonomy, name a new hybrid, re-recognize a species relegated to synonymy in recent decades, lectolypify and generally clarify nomenclatural issues in several genera, clarify taxonomy and distributions of species, and report important new and current distribution records. In IXodlingeria (Astcraceae), we clarify the taxonomy and distribution of IX sericocarpoides and IX umbcllata in the region. In Trilisa, we summarize and clarify the taxonomy of the genus Trilisa (Astcraceae), name a new hybrid in the genus, and present a new key to the taxa in the genus. Species delimitation in Stillingia (Fuphorbiaceae) has been controversial and unsettled in the region, and we examine the confused taxonomy and nomenclature of the genus Stillinpa (Huphorbiaceae) in the southeastern United Stales, rc-recog-nizinga species used byJ.K. Small, bul with an expanded circumscription and a clarification of various nomenclatural issues. We examine lypificalionof Desniodiumdinenii (Fabaceae) and its application to our modern understanding of the circumscription of taxa, recommending it be considered a junior synonym of Desmodium glabellum. Injuncus, we assign a lectotype for Juncus anlhelalus, clarifying its application. In Primulaccae, we discuss the delineation of genera in I.ysimachicac, and lake a middle path regarding lumping/splitting, supporting the recognition of traditional and monophyletic segregates Tricntalis, Steironema, Anagallis, Cenluncu/us, while treating l.ysimachia in a moderately broad sense, including Claux and multiple subcladcs; in order to implement this taxonomy in the southeastern United states, we make a single new combination in Steironema. We also discuss generic circumscription in Sclaginellaceae, and argue for the recognition at genus rank of six major clades, monophyletic, ancient, and morphologically recognizable; in order to apply this taxonomy in the southeastern United States, we make five new combinations in llryodesma. Gymnogynum, and Stachygynandrum. Finally, we report important new records of locally, regionally, or globally rare species in North Carolina: lklanlhium Icnellum, Chenopodium berlandkn var. macrooilycium, Carexbarraltii. Carexvestita. likocharis compressa var. compressa, Rhynchospora compressa, Rhynchospora sulcata, and Croton willdenowii.