NSF-PEET Project in Systematic Bryology

Revision of the Moss Genus Macrodictyum (Broth.) E. H. Hegew.  (Dicranaceae).

Michelle Judith Price

Missouri Botanical Garden


Introduction to Macrodictyum

Key to species in Macrodictyum

Illustrations of species in Macrodictyum

Distribution of Macrodictyum



Macrodictyum (Dicranaceae: Musci).

Macrodictyum is a small acrocarpous moss genus of three species. It grows in tufts or mats on trees, and rocks between 450-1500 m in the Neotropics. The genus has a restricted distribution within the Neotropics, and is currently known from only a few localities in Cuba, the Dominican Republic and southeastern Brazil.

The genus is monophyletic. It is characterized by: 1) sheathing perichaetial leaves; 2) 16 more or less undivided, fenestrate, papillose peristome teeth; 3) rhomboidal cells in upper leaf; 4) irregular, multicellular apical teeth; and 5) guide cells that are ventral at and above mid-leaf.. Back to TOP



Key to species in Macrodictyum


1. Leaves concave above, margins broadly incurved above             M. latifolium

1. Leaves tubulose or sub-tubulose above, margins not incurved above            2.

          2. Leaves oblong to lingulate, leaf apex obtuse, flagellate branches often       present.                                                                                       M. proliferum

          2. Leaves linear to narrowly oblong, leaf apex acuminate, flagellate branches absent.                                                                              M. wrightii

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Distribution of the genus Macrodictyum


Macrodictyum latifolium (circle), M. proliferum (triangle), M. wrightii (square).

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Michelle Price, Feb 2001