Cavan,
is the stem of Your plant glabrous, or hairy but not glandular? May be I'm wrong with the glandular hairs, I'll look with an amplifier tomorrow. At least the stem of my stinking Hygro is hairy and sticky.
Hygrophila senegalensis seems to be a similar species, the flowers look somewhat different, and the emersed leaves are narrower:
http://www.westafricanplants.sencken...e_id=14&id=834 http://www.aluka.org/action/showComp...A.SENEGALENSIS
According to "Flora of West Tropical Africa" "the lower leaves become pinnatifid, like those of Myriophyllum, if submerged":
http://www.aluka.org/action/showMeta....FWTA6776&pgs=
Probably also interesting for submersed cultivation.
EDIT: Submerged or submersed - what's correct? Both?