Morphology and Taxonomic Significance of Dormant Branch Primordia, Dormant Buds, and Vegetative Reproductive Organs in the Suborders Leucodontineae and Neckerineae (Musci, Isobryales)

Abstract

The manner of branch development and shape of vegetative reproductive organs were examined for 19families, 101 genera, and 227 species in the suborders Leucodontineae and Neck- erineae (Musci). Two types were recognized in the manner of branch development. They are distin- guished from each other by the nature of dormant condition: One with swollen primordia (type A) and the other with buds (type S). Filamentous pseudoparaphyllia always accompanied type A primordia, whilefoliose pseudoparaphyllia were always with type S. The presence ofscale-like leaves overarching buds was a good marker for recognizing the type S with ease. Each family and genus, with few exceptions, proved to be stable in the manner ofbranch development and shape of vegetative reproductive organs. Therefore, the two-character combination can be used as a new clue for the taxonomy of higher categories. Five genera, which are not closely related, have paraphyllia. The presence ofparaphyllia is correlated with the type S of branch development, and has no taxonomic significance. The familial affinities of two genera are considered; Henicodium is a monotypic genus and classified in the Pterobryaceae, and Penzigiella in the Neckeraceae. Several families of the Leucodontineae have long