Moroccan citron
The Moroccan citron was described by the Moroccan professor Henri Chapot, as being a sweet citron, meaning that its pulp is low in acid. He discovered that the acidity in the more common citrons or lemons, is represented by red on the inner coat of seeds specifically on the chalazal spot, violet pigmentation on the outer side of the flower blossom, and also by the new buds that are reddish-purplish. The Moroccan citron which is acidless is completely lacking the red color. This designation was cited by Herbert John Webber and Leon Dexter Batchelor the editors of the fundamental treatise on citrus, namely The Citrus Industry, which was published by the University of California, Riverside in 1967.
Diamante citron
The Diamante citron ("Citrus medica" var. "vulgaris" or cv. "diamante" − , or גינובה) is a variety of citron named after the town of Diamante, located in the province of Cosenza, Calabria, on the south-western coast of Italy, which is its most known cultivation point. This is why this variety is sometimes called the "Calabria Esrog". ""Esrog"" is the Ashkenazi transliteration of the Hebrew name for citron.
The Diamante citron was one of the most important varieties candied by the largest factories at Livorno, Italy; it was gathered from Liguria, Naples, Calabria & Sicily and then shipped into England and the United States.