Can someone ID this stem please?

[Oohitsae]

I recently got these stems in a plant package I bought from a seller on AB. He was out of a couple of different species of plants when I ordered so he replaced them with other species. He told me all the species he would replace the plants he was out of with before I paid and I recieved all of those species, but also got like 20 of these stems as a surprise! The seller asked me to send him a picture of this plant when I asked, but I forgot to up till last week, and haven't heard back. So I'm asking you guys, can you please help me ID this stem?

Thanks!!

 

[jetajockey]

Looks like hygrophila polysperma or one of it's close relatives.

 

[aqua_chem]

That was my first thought as well.

 

[Scottyhorse]

looks kind of like my Mexican Oak Leaf

 

[Oohitsae]

hmm I think that you guys are right!
Is there a common name for it?