Thank you for your question for eXtension. The topic area in which you've made a request is not yet fully staffed by eXtension experts and therefore we cannot provide you with a timely answer. Instead, if you live in the United States, please consider contacting the Cooperative Extension office closest to you. Simply go to http://articles.extension.org, drop in your zip code and choose the office that is most convenient for you. We apologize that we can't help you right now, but please come back to eXtension to check in as we grow and add experts.

I agree with the previous response.  The symptoms do appear to be those caused by a fungal pathogen such as Diaporthe, Colletotrichum, or Mycosphorella.  However, they appear to be limited to the latest flush and could be the result of a nutrient deficiency.  I have to wonder if this is the first time they have ever occurred?  Having said this, you should definitely attempt to get a diagnosis from a local citrus expert or pathologist to make sure you have not found something new in your grove.  This is pretty much the best advice I can give from so far away!