Brachytheciaceae

Hedenas, L., Huttunen, S., Shevock, J.R., Norris, D.H. (2009). Homalothecium californicum (Brachytheciaceae), a new endemic species to the California Floristic Province, Pacific Coast of North America. The Bryologist 112, 593-604. 

M.S., Devos, N., Vanderpoorten, A. (2008). Origin and evolution of the northern hemisphere disjunction in the moss genus Homalothecium (Brachytheciaceae). American Journal of Botany 95, 720-730. 

Ignatov, M. S. and Huttunen, S. (2002) Brachytheciaceae (Bryophyta) —A family of sibling genera. Amfoa, 11 245-296. 

FIGURE 6.2 The Brachytheciaceae clade from the single most parsimonious tree based on direct optimization analyses of molecular (cp psUY-R and tmh-P, and nr ITS2) and morphological data (based on Huttunen et ah, 2004). 

Once the main clades within the Brachytheciaceae had become more or less stabilized, our main goal was to elucidate the position of taxa not included or not well represented in the previous analyses, and also to find additional arguments for generic and subfamilial placement of some particular taxa. Three methods are involved here (1) evaluation of the molecular synapomorphies in POY alignment, i.e., characteristic indel events and substitutions (2) analysis of the secondary structure of the tmL intron and (3) phylogenetic analysis of a reduced dataset from previous analyses, with some additional taxa. 

The genera of Brachytheciaceae are quite diverse with respect to the level of substitution/indel events within the tmL intron (Appendices 6.1 and 6.2). Very few (0 to 3) substitution/indel events are observed in all members of the Homalothecioideae, most members of the Brachythecioideae (with the exception of Sciuro-hypmm and four species closely related to Brachythecium salebrosum, which have a long insertion), as well as basal groups of the Helicodontioideae (Squamidium clade),... 

It remains unclear if there are any environmental factors responsible for such a high level of substitutions in the Oxyrrhynchium-Donrichardsia clade and in the Sciuro-hypnum clade. The only correlation we could notice is that both groups are quite rich in eutrophic species, common on humus and decaying wood, which is somewhat less characteristic for other genera of Brachytheciaceae. 

Trachypus bicolor Reinw. Hornsch. AY044060 DQ200118 AF395624 Brachytheciaceae China, Hunan Prov., T. Koponen, S. Huttunen, S. Piippo P.-C. Rao 50721, 2. Oct. 1997 (H)... 

The Brachytheciaceae is a diverse group of mosses, and most of its representatives are mesic plants of forest floor, tree bases, fallen logs, rocks in forest, etc. The Brachytheciaceae have colonized two extreme habitats tree trunks, which led to many morphological parallelisms in sporophyte structure. 

Hedenas, L. (2002) An overview of the family Brachytheciaceae (Bryophyta) in Australia. Journal of the Hattori Botanical Laboratory, 92 51-90. 

Huttunen, S., Ignatov, M. S., Muller, K. and Quandt, D. (2004) Phylogeny and evolution of epiphytism in the three moss famihes Meteoriaceae, Brachytheciaceae, and Lembophyllaceae. In Molecular Systematics of Bryophytes (ed. B. Goffinet, V. HolloweU and R.MagUl). Missouri Botanical Garden Press, St. Louis, pp. 328-361. 

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