Ludwigia pulvinaris Gilg is regarded as a synonym of L. senegalensis, a marsh plant widespread in tropical Africa.12 Both taxa are now considered one species; in 1963 Raven had placed them together in their own section, Prieurea.2 Among aquarium ludwigias it is so far the only one with mostly three-merous flowers.23 As L. pulvinaris it was already kept in Germany from 1906: Hugo Baum raised it from seed of herbarium plants he had collected on the Kunene River (Angola) in 1899; it later disappeared from cultivation again.3
Submersed, the light green midrib of the light to blood-red, slightly bullate blades is striking; the shoots then grow ascending to erect and branch freely.2 This very difficult species requires plenty of CO₂, soft, acidic water and intense light.2 Under the name Ludwigia sp. 'Guinea' it returned to the aquarium hobby in the 2000s.23
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