|
The phylogenetic relationships of black-spored basidioid taxa (mainly coprinoid taxa) and an agaric-like gastroid taxon were studied. The sequences of internal transcribed spacer regions (ITS) partially including 17S, 25S and 5.8S from 14 species (Coprinus comatus, C. atramentarius, C. micaceus, C. cinereus, C. disseminates, C. rhizophorus, C. radians, C. echinosporus, Psathyrella candolleana, Podaxis pistillaris, Conocybe lactea, Bolbitius demangei, Agaricus balzei, and Stropharia rugosoannulata) were compared. The reciprocal homologies of ITS sequences among these species were in the range of 38.7∼77.2%. Black-spored taxa were classified into four clusters. Cluster Ⅰ comprised C. micaceus, C. radians, and C. disseminata. Cluster Ⅱ is consisted of C. cinereus, C. echinosporus, C. rhizophorus, and C. atramentarius. On the other hand, C. comatus is in cluster Ⅲ with Agaricus balzei and Podaxis pistillaris even though this species is belonging to the section Coprinus in morphological aspect. Psathyrelloid taxon is included in cluster II. The question of the origin of secotioid (agaric-like) fungi has been taken, though largely on theoritical suggestions as to whether gastroid taxa give rise to agarics with secotioid taxa as intermediates or whether secotioid taxa are evolutionary novelities arising from many distinct groups of agarics. In this relationship, it was shown that secotioid taxon evolved from within agaric species.
|