10. Gomphrena Linnaeus, Sp. Pl. 1: 224. 1753; Gen. Pl. ed. 5, 105. 1754.
[Latin gromphaena, a type of amaranth]
Steven E. Clemants
Herbs, annual or perennial. Stems ascending, decumbent, prostrate, or erect. Leaves opposite, sessile or petiolate; blade ovate to obovate, not fleshy, margins entire, long-pilose abaxially and sometimes adaxially. Inflorescences terminal and/or axillary, sessile, subglobose heads, often subtended by involucres of sessile leaves; bracts and bracteoles thin. Flowers bisexual; tepals 5, connate proximally; stamens 5; filaments connate basally into tube; pseudostaminodes absent; ovule 1; style 1, 1.5-4 mm; stigmas 2(-3), subulate or filiform. Utricles included in tepals, stramineous, ovoid or oblong, somewhat compressed, membranous, usually indehiscent. Seeds 1, lenticular, subglobose, to ovoid, smooth.
Species ca. 100 (9 in the flora): tropical, subtropical, and warm-temperate regions.
SELECTED REFERENCES
Holzhammer, E. 1955. Die amerikanischen Arten der Gattung Gomphrena Linné. I. Mitt. Bot. Staatssamml. München 2: 85-114. Holzhammer, E. 1956. Die amerikanischen Arten der Gattung Gomphrena Linné. II. Mitt. Bot. Staatssamml. München 2: 178-257.
