C. crispatula Engl. var. balansae (Gagnep.) Jacobsen, stat. et comb. nov.

C. balansae Gagnep., Not. Syst. 9: 131 (1941). - Lectotype (selected by Rataj, 1975): Balansa 264 (= 415), Chan Moi, 21.1.1921 (P, isotype K). Paratype: Kerr 5020, Tan Chum, 7.3.1921 (BK, K, P).

C. longispatha Merr., Journ. Arn. Arb. 23: 156 (1042). - Holotype: Petelot 2681, Phan Me, 12.11.1939 (GH).

C. kwangsiensis H. Li, Acta Phytotax. Sinica 15: 109 (1977). - Type: R.C. Ching 8505, Nanning, 2.12.1928 (Chung-Shan Univ., isotypes NY, W). Paratype: Ching 8504 (Chung-Shan Univ.).

Leaves 20 - 70 cm long, 1 - 4 cm broad, usually submerged, rather flaccid, green to brownish, slightly to strongly bullate (Figs. 2, 7 H, J – K, 19, 31, 32). Spathe with a long tube, 10 - 30 (-40) cm long, limb of spathe with a rather long and rather open spiral (Fig. 10 B, E).

Notes: Var. balansae develops into the largest and most spectacular of all the varieties when growing under optimal conditions, i.e. with leaves up to 70 cm long in a submerged state, the same plant being, however, only 10 - 15 cm tall when growing emerged. Besides the differences in leaf-size caused by growing conditions, there are also some forms that do not become as large and have darker leaves, just as forms with narrower leaves exist.

Var. balansae is found in central Thailand, northern Vietnam, and southern China.