Two species of Rickenella, R. indica and R. mellea, new to Japan

Abstract

The present study reports the identification of two newly recorded species of the genus Rickenella, R. indica and R. mellea, in Japan. Small (1-3 mm wide), parabolic to convex, and never becoming applanate or infundibuliform pileus are characteristic features of R. indica. Rickenella mellea is a subalpine species and it is characterized by its honey-colored, yellowish-beige to reddish yellow-pileus and stipe. Molecular phylogenetic analysis using the ITS region and the LSU of the nuclear rDNA supported their identification based on morphological observations. A key to the known Japanese species of Rickenella and morphologically similar taxa is provided.