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Leptodon corsicus (Neckeraceae) is described as the first endemic moss species from Corsica. It strikingly differs from the other species of the genus by the lack of a dense and pinnate to bipinnate mode of branching; about 10 times smaller shoots that do not inroll upon drying; the lack of paraphyllia; and few, occasional small pseudoparaphyllia. Due to its small size and several leaf characters, L. corsicus shares at first glance more similarities with Homalia webbiana and Neckera besseri than with Leptodon. Yet, phylogenetic analysis of chloroplast and nuclear DNA sequences unambiguously shows that L. corsicus is deeply nested within L. smithii. The numerous morphological characters that distinguish L. corsicus from L. smithii cannot be attributed to plasticity. Consequently, we interpret the phylogenetic position of L. corsicus as the result of a recent speciation process, involving mutations at one or a few coding loci or differences in gene expression, which have tremendous consequences for phenotypic appearance, and retention of ancestral polymorphism in the non-coding sequences used for phylogenetic reconstruction. Such an explanation might also apply to other species of mosses, which exhibit a striking morphology, and yet share identical non-coding sequences with the common species they derive from. The notion of species in mosses is discussed in this context. [ABSTRACT FROM AUTHOR]

Fossombronia caespitiformis subsp. multispira has been found at Gozée (province of Hainaut, Belgium), 330 km outside its known range. This subspecies is characterised by elaters having 3-4 spirals. The plants from Gozée correspond well with the original description of Fossombronia husnotii, a synonym of this subspecies. As the rhizoids are purple, not colourless as those traditionally described for F. husnotii, rhizoid colour is not a reliable character to distinguish F. caespitiformis subsp. multispira. [ABSTRACT FROM AUTHOR]

Testing whether rare species are limited by narrow habitat conditions from correlations between species occurrence and measured environmental factors is usually hampered by the lack of statistical power associated to the low number of observations. Aneura maxima is an exceedingly rare liverwort in Europe whose recent discovery precluded the inclusion within the Red Data Book of European bryophytes. A series of new observations resulting from intensive bryophyte grid-mapping at the border between France and Belgium allowed the statistical investigation of the factors accounting for its distribution at the landscape scale. The species was systematically observed in deep ravines on damp, loamy soils under light tree cover within broadleaf woodlands. These conditions differ from those of other European localities, suggesting that A. maxima is not limited by a narrow ecological range. Attempting to predict the occurrence of A. maxima at the landscape scale from data on land use and soil conditions resulted in a model where the species was actually observed in only a half of the squares where its probability of occurrence was the highest. The species thus does not seem to have colonized all its potential habitats, which may be explained by the poor dispersal ability of this dioecious, rarely fertile species. Given the relative frequency of A. maxima in the Semois river basin, but taking into account its seemingly low dispersal ability and its preference for swampy habitats that are threatened by draining and spruce plantations, a status as 'conservation dependent' to 'near threatened' within the category 'lower risk' is proposed. [ABSTRACT FROM AUTHOR]

An analysis of DNA sequences in the ITS region of nrDNA and the atpB-rbcL intergenic spacer has placed Brachythecium appleyardiae McAdam & A.J.E.Sm. within a strongly supported clade in the genus Scleropodium. This position is consistent with the morphology and growth-form of B. appleyardiae. Specimens of the latter are similar to S. cespitans (Wilson ex Müll. Hal.) L.F. Koch but appear to differ in their narrower leaf-shape and the tendency to occur on dry rock ledges. However, measurements of a range of specimens from Britain and Ireland show that there is no clear discontinuity between the two taxa. Consequently, B. appleyardiae is reduced to synonymy with S. cespitans. [ABSTRACT FROM AUTHOR]