Tuber Aestivum (Black Summer). Available May to August.
Resemble the Winter Truffles a lot, but are usually bigger and tougher.
They are best used fresh. Black Truffles are also usually cheaper than the White because of their durability. Both can be preserved in oil or be frozen.
Although less strongly flavored than the winter truffles, these are regarded as a fine dish ingredient by many truffle enthusiasts.