Syngonanthus sp. 'Manaus'

Syngonanthus sp. 'Manaus' is a trade name listed here as a synonym of Syngonanthus cf. inundatus; the plant was introduced as Tonina sp. 'Manaus'.¹² The “cf.” reflects an uncertain identification: a comparison with the isotype of S. inundatus does point to this species, but no inflorescence was available for it.¹ According to the botanical world checklist, S. inundatus is a synonym of S. appressus, which is native to west-central and south-eastern Brazil.³

In the aquarium this stem plant from South America is regarded as demanding; strong light, CO₂ supplementation and soft, rather acidic water are recommended, and it can also grow emersed.¹⁴ In the forum one aquarist describes leaf heads of approx. 4.5 cm; two aquarists report brisk growth, one of them even with heavy algae in the tank.⁵

1. Syngonanthus cf. inundatus – Flowgrow Aquatic Plant Database (accessed 5 October 2026)
2. Syngonanthus – Aquarium and Pond Plants of the World (APPW), USDA APHIS (accessed 5 October 2026)
3. Syngonanthus appressus – Plants of the World Online, Royal Botanic Gardens Kew (WCVP data as of 4 June 2026, accessed 5 October 2026)
4. Syngonanthus cf. inundatus – Knowledge Base, The Barr Report (accessed 5 October 2026)
5. Thread “Syngonanthus-Arten” – Flowgrow forum (accessed 5 October 2026)