Citrus x pyriformis
This hybrid pomelo/citron is much larger than a normal lemon, with fruits reaching upwards of 5 lbs each. Not particularly cold hardy, protect in northern Florida and during times of extreme cold in the rest of Florida. The scientific name contains an x indicating that the species is a hybrid of two or more different species, and refers to the genus, Citrus, with “pyriformis” meaning pear-shaped.
Tampa Bay Chapter Rare Fruit Council International 