Callitriche raveniana Lansdown

Plants terrestrial. Petiole 1.3-1.5 mm; leaf blade expanded, 2-2.5 × 0.5-0.8 mm; venation simple, generally limited to 1 primary and a pair of secondary veins with occasionally few branches arising from secondary veins. Flowers solitary, usually a carpellate and staminate flower in each axil; bracts persistent 0.2-0.3 mm; styles 0.2-0.3 mm; filaments 0.2-0.3 mm; anthers ca. 0.2 × 0.2 mm; pollen spherical to ellipsoid, yellow, ca. 20 × 18-20 µm. Fruits 0.6-0.9 × 0.8-1.3 mm, wider than high, subsessile to shortly pedunculate, winged throughout; wing 0.07-0.1 mm wide at apex, 0.05-0.08 mm wide at side.

Taiwan.

● Streamsides, wet soil, roadsides; near sea level to 300 m.