Concerning the Symbol of the Arche Seleukeia

[Hax]

Hello,

Today I have a question directed to everyone that has some knowledge about the history of the Arche Seleukeia

https://i187.photobucket.com/albums/...eSeleukeia.jpg

I've come across this symbol more than once, both in RTR and in EB, but I was wondering what it represents, when I saw it first I thought it was an anchor turned upside down.

So what does the symbol represent? I do know of course what the rest of the Diadochi had, the Eagle of Ptolemaic Egypt, the Argeade Sun of Pella and Makedonia, etc.

Where did this symbol of the AS originate, why specifically this symbol, etc.

So what's up with the Arche Seleukeia?