Nomaphila siamensis

Nomaphila siamensis is a synonym of Hygrophila corymbosa, a member of the acanthus family from South-East Asia that has been introduced in Florida and north-eastern Mexico.¹⁴ In the aquarium hobby “siamensis” stands for the Thai hygrophila, a light green or reddish brown growth form with narrowly lanceolate leaves 10–20 cm long when submersed.²⁴

It is robust, fast-growing and modest in its light requirements; well fertilised and brightly lit it becomes more compact and slightly bronze.²³⁴ It suits groups in the midground and background and is easily propagated from shoot tips.² Submersed this is far more productive than in the often confused H. ringens.⁵ Emersed it flowers readily, in shades of blue to lilac.²⁴

1. Hygrophila corymbosa – Plants of the World Online, Royal Botanic Gardens Kew (WCVP data as of 4 June 2026, accessed 5 October 2026)
2. Hygrophila corymbosa “Siamensis” – Flowgrow aquatic plant database (accessed 5 October 2026)
3. Hygrophila corymbosa – Tropica Aquarium Plants (accessed 5 October 2026)
4. Kasselmann, C. (2019): Aquarienpflanzen. 4th edition (German). - Ulmer Verlag, Stuttgart: pp. 382–383.
5. Kasselmann, C. (2019): Aquarienpflanzen. 4th edition (German). - Ulmer Verlag, Stuttgart: p. 393.