Phylogenetically speaking, which came first, the lemon or the lime?

Citrus phylogeny is hard to pin down, because there has been so much hybridization over the centuries, but it seems that some lime species are among the original citrus species, while all lemon species have been produced by hybridization. This would make lemons phylogenetically more recent.
https://en.wikipedia.org/wiki/Citrus#cite_note-1

It also appears that there is more diverse phylogenetic development in limes that in lemons, again suggesting that they have been around longer in the citrus gene pool.
springerlink.com/content/tjggcl5wyyu6l69d no longer exists

However, it is stated in another Wikipedia article that lemons grew wild in Asia.
https://en.wikipedia.org/wiki/Lemon

Yes, it seems that limes came first, though table 2 of the last link below indicates that lemons have been as food longer than limes.
Citron medica is the fruit species from which both originated and as you indicated, the diversity of lime species makes it older than the lemon.
I was hoping that somebody had a copy of a (very old) National Geographic in which they featured "Fruits of the World". There, I read that limes were definitely older than lemons and that in fact, lemons were hybridized from limes. It was probably from before 1950, though I bought my copy recently at a library book store and has since disappeared. That feature on fruits was so extensive that it was covered on two consecutive issues of the magazine.

http://www.hort.purdue.edu/newcrop/morton/lemon.html
http://www.hort.purdue.edu/newcrop/morton/mexican_lime.html
http://www.answers.com/topic/cit-rus