I noticed this herb in a coastal sandy beach. Please help to identify this Rubiaceae member.
Is this Hedyotis graminifolia L.f. var. graminifolia ?
I too think this plant is Hedyotis graminifolia L.f. var. graminifolia a vey common plant in Eastern Ghats as well in West bengal.
Looks different from Oldenlandia stricta L. as per eflora of Karaikal Dist (Images and specimen) GBIF (high resolution specimens)
yes you are 100% right, it is Oldenlandia umbellata,
because of environmental conditions it looks slightly variable