东方水韭 dong fang shui jiu

Plants aquatic, emergent. Rhizome 3-lobed. Microphylls 20-40 tufted, widely spreading, white at base, green above, spirally arranged, 10-20 cm, ca. 2 mm wide at middle, flattened on adaxial side, rounded on abaxial side, base alate; peripheral fibrous bundles present; central intrastelar canal 1. Ligules ovate-subtriangular, 1.5-2 × 2-3 mm. Sporangia basal, obovate, 5-6 × 3.8-4.5 mm; velum rudimentary, covering only distal edge of sporangium. Megaspores white when dry, gray when wet, 350-450 μm in diam., proximal hemisphere cristate with muri irregularly anastomosing, distal hemisphere cristate-reticulate. Microspores gray en masse, elliptic, 19-29 μm in diam., spinulose-verrucate and granular. Spores mature Jun-Oct. 2n = 66*.

● Swampy and loamy meadows between hills; ca. 1200 m. Zhejiang (Songyang).

Iseotes orientalis is an allohexaploid. It occurs within the range of I. sinensis, and it appears to be a hybrid between I. sinensis and I. yunguiensis or a closely related taxon.