Italy has many different varieties, but there's not a lot of difference between them. Timo serpillo (Thymus serpyllum) is wild thyme, also known as pepolino, pipernia or timo selvatico.
It can also mean the thymus gland—sweetbreads, usually from a calf (ris de veau) or lamb (ris de agneau), sometimes used with porcini mushrooms on crostini.
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