Ceriporia pierii Rivoire, Miettinen & Spirin sp. nov. Figure 11

Holotype.

France. Rhône-Alpes: Vernaison, Populus nigra, 24 Sep 1995, Rivoire 1161 (H, LY).

Etymology.

Named after Max Pieri, who with Bernard Rivoire first discovered this species.

Description.

Basidiocarp 0.2-1 mm thick, 1-4 cm in the widest dimension. Sterile margin narrow (up to 1 mm wide). Pore surface cream-colored to rosy, in well-developed basidiocarps with apricot tints, pores 2-3(4) per mm, dissepiments mostly entire. Subicular hyphae more or less parallel to substrate, (5)5.1-8.2(9.1) µm in diameter; a few hyphae bearing incomplete clamps or inflated portions. Tramal hyphae 4-5.2 µm in diameter. Subhymenial hyphae 2.9-4 µm in diameter. Basidia 13.8 –19.3×4.4– 5.2 µm . Basidiospores ellipsoid to rarely cylindrical, ventral side flat or slightly concave, (3.9)4.1 –5.4(6.1)×2.4– 3.1(3.2) µm, L=4.72 µm, W=2.77 µm, Q=1.70.

Remarks.

Ceriporia pierii is introduced here to encompass Ceriporia davidii sensu Pieri and Rivoire (1997). Pieri and Rivoire identified Ceriporia camaresiana (Bourdot & Galzin) Bondartsev & Singer as the most similar species to Ceriporia pierii, but our data show that the two are not closely related (Figure 2). Basidiospores of Ceriporia camaresiana are clearly curved, mostly bean-shaped and longer, 5.26 × 2.74 µm (Table 5). Moreover, the hyphal structure is different: in Ceriporia camaresiana hyphae are mostly long-celled and not inflated, covered with small resinous droplets, and their diameter is approximately the same in all parts of the basidiocarp (3-4 µm in trama and 4-5 µm in subiculum).