Newly recorded in the Netherlands—IV. Poria xantha

Polyporus xanthus Fr. per Fr., Syst. mycol. 1: 379. 1821. — Poria xantha (Fr. per Fr.) Cooke in Grevillea 14: 112. 1886. — Amyloporia xantha (Fr. per Fr.) Bond. & Sing. ex Sing. in Annls. mycol. 39: 50. 1941. — Poria xantha (Fr. per Fr.) Cooke f. pachymeris Jo. Erikss. in Svensk bot. Tidskr. 43: 22. 1949. — For other synonyms see Donk (1974: 164). Fruit-bodies perennial, resupinate or on vertical surfaces also in the shape of dimidiate, conical pilei, up to 15x10x15 mm, made up of indistinctly stratified tubes. The young, wide lower part of the pilei light yellow to pale orange, the old, narrow upper part greyish and zonate. Fruit-bodies fibrous when young, becoming brittle, then friable or even chalky with age. Margin at first sterile, white, arachnoid, later forming a fertile, well-defined edge. Subiculum white, up to 1 (-2) mm thick, strongly amyloid. Tubes up to 5 mm long, with entire edges. Pores about circular, 0.05-0.15 mm in diameter, sometimes elongated to 0.5 mm, 4-9 per mm. Dissepiments 0.05-0.1 mm thick, pseudo-amyloid (colouring golden yellow to reddish brown) or weakly amyloid. Fruit-bodies with distinct lemon odour when fresh according to collectors of specimens from Olst (see below), aromatic according to others; at first mild, then very bitter.