Background and Purpose: The species diversity within the genus Tuber is a highly mysterious. The aims of this study are to give detailed taxonomical, morphological and ecological characteristics of the new species Tuber decipiens. Material and Method: Based on fungarium studies, field observations and historical review, morphological studies have been conducted on the species. The recording morphological details were carried out using a microscope. Results and Conclusions: Tuber decipiens is a black colored truffle and a new species belonging to order Pezizales and family Tuberaceae. It was found in autumn (November-December 2010) near the Adriatic Sea (Rovinj, Croatia) and grows in pure pine forest (Pinus halepensis) in the calcareous-gravel soil (pH 7.5-7.8). Tuber decipiens is different in the morphological and other characteristics from all the other known black. The new species is most similar to the winter truffle Tuber brumale var. moscatum which grows in autumn and winter in symbiosis with deciduous trees. Unlike the winter truffle, a new species (Tuber decipiens) grows in symbiosis with Pinus halepensis and permanently has a basal depression with one or more cavities, clearly visible in the cross section of fruitbodies. Very important characteristics are the color of gleba, which is never blackish or black and in mature fruitbodies remains gray-brownish, the asci are spherical or very rarely ovoid-ellipsoid, containing 1-6 spores. The odor of the new species is not pleasant and reminiscent of the soil or mould while the odor of Tuber brumale yam: moscatum is delicate and persistent, and reminiscent of the musk. Tuber decipiens, a new species from Croatia is described.
