Nymphoides macrospermum

{{Short description|Species of flowering plant}}

{{Use dmy dates|date=August 2019}}

{{Speciesbox

| image =

| status = CR

| status_system = IUCN3.1

| status_ref = {{Cite journal | author = Karuppasamy, S. | author2 = Rao, M.L.V. | name-list-style = amp | title = Nymphoides macrospermum | journal = The IUCN Red List of Threatened Species | volume = 2011 | page = e.T194159A8885335 | publisher = IUCN | date = 2011 | url = http://www.iucnredlist.org/details/194159/0 | doi = 10.2305/IUCN.UK.2011-1.RLTS.T194159A8885335.en | access-date = 15 January 2018| doi-access = free }}

| genus = Nymphoides

| species = macrospermum

| authority = Vasud.Nair

| synonyms =

}}

Nymphoides macrospermum is a critically endangered aquatic plant of the family Menyanthaceae endemic to Alwaye in Kerala, India. It is an annual herb which has been observed in paddy fields, lagoons and slowly flowing streams. It is dioecious, with male and female flowers on separate plants.{{cite journal|doi=10.1600/036364411X605092|title=Phylogenetic Relationships and Morphological Evolution in Nymphoides (Menyanthaceae)|year=2011|last1=Tippery|first1=Nicholas P.|last2=Les|first2=Donald H.|journal=Systematic Botany|volume=36|issue=4|pages=1101–1113|s2cid=83643283}}