There has been ongoing controversy over the taxonomy of Pleurochaete in North America. Some authors have recognized two species (P. luteola and P. squarrosa), whereas others have argued that these intergrade and should be treated as one species. Our examination of variation in the acknowledged key character, extent of the hyaline basal cells up the leaf margin, revealed a clear separation of New World plants into two groups. Geographical and ecological differences parallel the morphological variation, and extent of the hyaline margin appears to be a stable character that does not consistently vary with plant size, leaf length, or stressful environments as proposed by some authors. Evidence from other studies employing chloroplast and nuclear genomic markers lends support to the recognition of two distinct lineages in the New World. Moreover, these studies indicate that New World populations of “P. squarrosa” are not conspecific with Old World P. squarrosa, as many authors have assumed. Naming of the New World populations of “P. squarrosa” should await a thorough study that simultaneously analyzes both morphological and genetic variation.
The diversity of the liverwort genus Porella is studied in the Govind Wildlife Sanctuary (GWLS), Uttarakhand. A total of 12 species and infraspecific taxa are described, all being reported for the first time from the area. A working key is provided for identification along with the taxonomic description of each of them. As Porella is represented by 23 species and infraspecific taxa in the Western Himalaya, the number of species and infraspecific taxa found in Govind Wildlife Sanctuary is relatively high.
Type material of two Australian species: Trichocolea minutifolia Steph. and T. wattsiana Steph. is critically reviewed. On the basis of morphological observations both species are considered to be conspecific with T. hatcheri E.A.Hodgs., a species distributed in Australia and New Zealand. Detailed descriptions and illustrations based on the holotype are also provided for T. rigida R.M.Schust., the species newly confirmed on Macquarie Island. The worldwide key to the species of Trichocolea is given for the first time.
The phylogenetic position of the East Asian monospecific genus Hattoria has been controversial since its description in 1961. Over the years it has been considered as either a member of subfam. Jamesonielloideae in Lophoziaceae/Jungermanniaceae, subfam. Jungermannioideae in Jungermanniaceae, or Anastrophyllaceae, due to its morphological characters related to the genera with unlobed leaves, such as Jamesoniella, Scaphophyllum or Gottschelia. In the present study we provide molecular evidence that supports its inclusion in the family Anastrophyllaceae and Hattoria as a distinct genus resolved and nested in a Tetralophozia–Plicanthus clade. Our phylogenetic analyses suggest that unique morphological characters, such as unlobed and entire leaves and bracts shown in Hattoria, be considered an autapomorphy for the genus/species and also support recognition of the genus Hattoria as distinct from the other genera of the family. Some sporophyte characters including morphology of the seta are newly given for Hattoria yakushimensis (Horik.) R.M.Schust.
In Japan 655 species in 142 genera of liverworts and 17 species in 6 genera of hornworts are recognized. Many nomenclatural changes, a number of new species and infraspecific taxa (subspecies or varieties) of liverworts and hornworts have been reported for the Japanese flora since our previous checklist published in 2012 which recognized 625 species in 146 genera of liverworts and 17 species in 6 genera of hornworts. Phylogenetic arrangement for Japanese liverwort and hornwort genera are provided and current accepted names of Japanese liverworts and hornworts are alphabetically listed with annotations. In the annotations, the taxonomy, nomenclature and synonymy of many of the accepted species and infraspecific taxa are discussed briefly, based primarily on recent literature sources published up to 31st December 2017 and the authors’ observation. Homotypic (nomenclatural) synonyms are indicated in the annotations by the symbol ≡and heterotypic (taxonomic) synonyms by the symbol ＝. Three new combinations: Solenostoma granulata (Steph.) T.Katag. & Furuki, Solenostoma orientale (Bakalin & Vilnet) T.Katag. & Furuki, and Solenostoma shinii (Amakawa) T.Katag. & Furuki are proposed. Dendrocerotales T.Katag. & Furuki, which lacked description since described, is formally validated. Pleurozia gigantea (F.Weber) Lindb. is excluded from the Japanese flora, because the original citation of the species from Japan turns out be an error. Information on fossil species of Japanese liverworts and hornworts including two liverwort species are also summarized.