ID this plant!

[G H Nelson]

Hi
Aquatic botanists.
Purchased this stem as Ludwigia arcuate?
I'm not convinced looks like a Alternanthera although I could be wrong!

hoggie

 

[Mick.Dk]

Look like L. arcuata.
I would have liked to see even more narrow leaves, though - but this is likely a matter of conditions in tank. Colour of upper-side pf leaves worry me a bit, too.
To be sure, you can ofcourse do the emerse version. Leaves of L. arcuata will change a lot emerse.
Both L. arcuata and most of the common Alternanthera are easy to grow emerse and willingly flower. Flower are very different, as you can google-check........

 

[G H Nelson]

Confirmed as Alternanthera by the seller....