A REVISION OF THE MOSS GENUS SCIAROMIUM (MITT.) MITT. III. THE SECTION PLATYLOMA BROTH.

抄録

  The section Platyloma Broth. in Engl. & Prantl of Sciaromium (Mitt.) Mitt. included only Sciaromium lescurii (Sull. in Gray) Broth. in Engl. & Prantl, a species endemic to eastern North America. The species is fully described and illustrated and a detailed map of its distribution is provided. The separate genus, Platylomella Andrews, is restored in order to accommodate it. Platylomella is distinct from all rheophytic taxa with limbate leaves on the basis of bistratose leaf margins and the presence of filiform paraphyllia. Sciaromium laxirete A. Abr. & I. Abr., a fossil from the Pliocene deposits of Bashkiria in the Soviet Union, is transferred to Platylomella and placed, with some reservation, in synonymy with P. lescurii. The relationships of Platylomella are discussed and the genus is transferred to the Hypnobartlettiaceae.