A REVISION OF THE GENUS LEUCOBRYUM (MUSCI) IN ASIA

Abstract

  Based on a taxonomic revision of the genus Leucobryum in Asia, after examination of about 3000 specimens including types, the following important taxonomic characters were newly recognized: (1) central strand of stem, (2) proration of abaxial side of leaf acumina, (3) decurrency of abaxial leucocysts, (4) ratio between thickness of the thickest part and thickness of the median furrow in the cross-sections of leaves, (5) position of perichaetia, (6) ratio between length of the matured inner perichaetial leaf and length of the stem leaf near the perichaetium, (7) length of archegonia, (8) presence of normal male plants, and (9) growing position of dwarf male plants. Among the 78 taxa reported from Asia, 33 taxa were newly reduced to synonyms, 4 taxa were newly reduced to lower status, 2 taxa were excluded from the Asian bryoflora, 4 taxa were combined with other genera, and the following 19 taxa were recognized as Asian Leucobryum. (1) Leucobryum javense (Brid. ex Schwägr.) Mitt., (2) L. javense var. cyathifolium (Dix.) T. Yamaguchi, stat. nov., (3) L. javense var. novae-guineae (Bartr.) T. Yamaguchi, slat. nov., (4) L. javense var. uncinatum (Fl.) T. Yamaguchi, stat. nov., (5) L. scabrum Lac., (6) L. aduncum Dozy & Molk., (7) L. aduncum var. teysmannianum (Dozy & Molk.) T. Yamaguchi, stat. nov., (8) L. aduncum var. scalare (C. Müll. ex Fl.) A. Eddy, (9) L. chlorophyllosum C. Müll., (10) L. boninense Sull. & Lesq., (11) L. juniperoideum (Brid.) C. Müll., (12) L. humillimum Card., (13) L. imbricatum Broth., (14) L. glaucum (Hedw.) Ångstr. in Fries, (15) L. bowringii Mitt., (16) L. sumatranum Broth. ex Fl., (17) L. sericeum Broth. ex Geh., (18) L. sanctum (Brid.) Hampe and (19) L. arfakianum C. Müll. ex Geh. For each species synonymy is given together with pertinent literature along with its type, detailed description and illustration, discussion on taxonomical status, selected specimens examined and geographical distribution.