Gratiola amphiantha

D. Estes & R. L. Small

Syst. Bot. 33: 181. 2008.

Common names: Pool sprite snorkelwort
EndemicConservation concern
Basionym: Amphianthus pusillus Torrey Ann. Lyceum Nat. Hist. New York 4: 82. 1837
Treatment appears in FNA Volume 17. Treatment on page 266. Mentioned on page 264, 265.

Annuals. Stems erect, simple or few-branched, (7–)9–21(–29) cm, glabrous or glabrate proximally, glabrate or glandular-puberulent distally. Leaves: dimorphic, submersed basal and clustered, floating paired at ends of branches to 70 mm, blade of submersed lanceolate to oblanceolate or oblong, 1–7 × 0.5–3 mm, margins entire, apex obtuse to acute, surfaces glabrous, blade of floating elliptic to ovate or nearly round, 3–10 × 2–9 mm, margins entire, apex obtuse to rounded or retuse, surfaces glabrous. Pedicels stout, 0.1–3 mm, length less than 0.1 times bract, glabrous; bracteoles 0. Flowers: sepals connate proximally, calyx lobes obovate to oblong, 0.7–1 mm; corolla 3–4 mm, tube and limb white tinged pink or purple, veins lavender or purple; style 0.5–1 mm. Capsules bilaterally symmetric, obcordiform, 2–3 × 3–4 mm. Seeds (0.3–)0.4–0.5 mm. 2n = 18.

Phenology: Flowering Mar–Apr.
Habitat: Shallow, ephemeral pools on exposed granite outcrops.
Elevation: 100–300 m.


Phylogenetic studies confirmed that Gratiola amphiantha, long treated in monospecific Amphianthus, is embedded in Gratiola (D. Estes and R. L. Small 2008). Gratiola amphiantha is listed as a federally-threatened species by the United States Fish and Wildlife Service.

Selected References


Lower Taxa