I actually made a drawing about green ponies some time last year…may or may not post it in the future. Turns out there are quite a few of them, most of them earth ponies, understandably.
 
Also, does Thorax now count as a green…pony? Or no, since he’s a changeling?

@OneOverTwo  
The two big problems with obscure references:  

@Corrderio  
Did you… not get the reference?

I think a possible reason for why there aren’t many green ponies is because the background is often green grass.
 
However, I really personally wish for more green ponies. Green is my favorite.

No one recognizes Merry May or many many Apple Family members. :(
 
@Mildgyth  
Technically, Sprinkle Medley is blue. Her hue is greater than 180° (around 184-185°) which leads to a blueish color.

@Thanotos Omega  
This, though I’d replace creative with good

@Background Pony #2B2C  
No, she’s minty.
 
 
THIS, however, is hot.

Green doesn’t sell well as a toy color, or so Hasbro said some years ago.

What about Junebug?

I thought Lyra was more Aqua (Blueish-Green), myself.

@EddersCPFC  
I will though mint color as generalized green. But still very few.

@EddersCPFC  
She’s hot

There’s also Minty Bubblegum
 

 
But like Lyra, she’s mint (obviously :P)

I would’ve described Lyra more as a turquoise colour.
 
@Mildgyth  
This one too.
 
It’s true, there aren’t as many green ponies. For some reason, it’s not considered to be as good a colour for our favourite pones as other parts of the rainbow; I’m not sure why, that’s just what the creators think probably, therefore they create less green pones and therefore a lot of fans like them just a bit less because there are less of them; it’s a self-perpetuating myth, I guess. *le shrug*
 
Also…
 
@Background Pony #2B2C  

 
Whoaaaaa…a colour map of most (if not all) of the ponies? That’s just a little bit AWESOME! :D

There’s also green-mane’d Carrot Top:  

#GreenPoniesMatter

Beacuse green isn’t your color.

True  

Green’s a nice color, but it isn’t a nice pony color.

Green Jewel  

 
Apple Honey  

Best color. If you disagree, get out of town

Because it is not a creative color,

And technecially Lyra is mint. Not very pure green.