Cantharellus chicagoensis sp. nov. is supported by molecular and morphological analysis as a new yellow chanterelle in midwestern United States.

Recent molecular systematic studies of Cantharellus cibarius sensu lato have revealed previously unknown species in different regions of North America. This study investigates yellow chanterelles in the Midwest using phylogenetic analysis of three DNA regions: nuc rDNA internal transcribed spacer 2 (ITS2) and 28S sequences and translation elongation factor 1α gene (EF1α). This analysis reveals a locally common taxon Cantharellus chicagoensis sp. nov. as distinct from sympatric species present in northeastern Illinois, northwestern Indiana and Wisconsin. This chanterelle features a pileus that often has a greenish yellow margin when immature, a squamulose disk when mature, a yellow spore print and the absence of a fragrant odor. Multiple Cantharellus specimens group with C. flavus and C. phasmatis, expanding their known range, and others with C. roseocanus Our observations highlight the diversity of Cantharellus in midwestern USA and further document the need for additional systematic focus on the region's fungi.