Lemon Tree fllower

I have a lemon tree that has not have fruits, and I think it is caused by some insect or I don´t what, is damaging the flower.
So I am attaching a flower where you can see what I mean:
I hope someone is able to tell me what to do.
Thank you

 

I've seen this before - on my citrus trees it's caused by ants.

 

Lorax, unless the ants are tiny tiny, because I have been observing all day, at different hours and when the sun goes down, and I have only seen bees.
I will look more carefuly for tiny ants
Lorax thank you!

 

It's natural unless all the flowers are like this. My Ponderosa lemon and Etrog citron both produce significant numbers of these incomplete flowers. According to Webber,

 

JK, not all the flowers but many of them.
Since it has a brown burnt like dot, I thought it was an insect.
Your article is excelent and I learned by reading it.
Thank you very very much