- Scientific Name: Potamogeton cristatus Regel & Maack
- Ref: Mém. Acad. Imp. Sci. Saint Pétersbourg, sér. 7. 4(4) [Tent. Fl. Ussur.]: 139. 1861.
- Synonyms: Potamogeton iriomotensis Masam.
- English Common Name: little-leaf pondweed
- Chinese Common Name: 鸡冠眼子菜 jī guān yǎn zǐ cài
- Japanese Common Name: コバノヒルムシロ
- Family: Potamogetonaceae
- Genus: Potamogeton
- Distribution: Ponds, paddy fields. Anhui, Fujian, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Liaoning, Sichuan, Taiwan, Zhejiang [Japan (including Ryukyu Islands), Korea, Russia].
- Type: Am mittleren Ussuri bei Buldschi, in Lagunen und kleinen Seen gesellschaftlich mit P. pusillus wachsend. Mitte Juli mit Blumen und Früchten.
Plants annual or perennial, in fresh water. Rhizome inconspicuously present or absent. Stems filiform, terete, ca. 0.5 mm in diam., simple or sparsely branched; dormant turions axillary, narrowly fusiform, with 3-5 acerose leaves. Leaves dimorphic; stipules convolute, 6-10 mm, membranous, free from leaf base. Submerged leaves sessile, linear to filiform, 2.5-7 cm × ca. 1 mm, 3-veined. Floating leaves usually alternate, opposite just below peduncle, petiolate; petiole 1-1.5 cm; blade opaque, ovate to ovate-oblong, rarely lanceolate, 1.5-2.5 cm × 3-11 mm, leathery, 7-veined, base rounded or cuneate, apex acute or obtuse. Spikes with 3-5 whorls of opposite flowers; peduncles 0.8-1.5 cm. Carpels 4. Fruit obovoid, 1.5-2.5 mm, laterally compressed and shortly pedicellate, abaxial keel cristate; beak 1-1.2 mm, slender. Fl. and fr. May-Sep.(Flora of China)