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Earlier phylogenetic studies, including species belonging to the Neckeraceae, have indicated that this pleurocarpous moss family shares a strongly supported sister group relationship with the Lembophyllaceae, but the family delimitation of the former needs adjustment. To test the monophyly of the Neckeraceae, as well as to redefine the family circumscription and to pinpoint its phylogenetic position in a larger context, a phylogenetic study based on molecular data was carried out. Sequence data were compiled, combining data from all three genomes: nuclear ITS1 and 2, plastid trnS-rps4-trnT-trnL-trnF and rpl16, and mitochondrial nad5 intron. The Neckeraceae have sometimes been divided into the two families, Neckeraceae and Thamnobryaceae, a division rejected here. Both parsimony and Bayesian analyses of molecular data revealed that the family concept of the Neckeraceae needs several further adjustments, such as the exclusion of some individual species and smaller genera as well as the inclusion of the Leptodontaceae. Within the family three wellsupported clades (A, B and C) can be distinguished. Members of clade A are mainly non-Asiatic and nontropical. Most species have a weak costa and immersed capsules with reduced peristomes (mainly Neckera spp.) and the teeth at the leaf margins are usually unicellular. Clade B members are also mainly non-Asiatic. They are typically fairly robust, distinctly stipitate, having a single, at least relatively strong costa, long setae (capsules exserted), and the peristomes are well developed or only somewhat reduced. Members of clade C are essentially Asiatic and tropical. The species of this clade usually have a strong costa and a long seta, the seta often being mammillose in its upper part. The peristome types in this clade are mixed, since both reduced and unreduced types are found. Several neckeraceous genera that were recognised on a morphological basis are polyphyletic (e.g. Neckera, Homalia, Thamnobryum, Porotrichum). Ancestral state reconstructions revealed that currently used diagnostic traits, such as the leaf asymmetry and costa strength are highly homoplastic. Similarly, the reconstructions revealed that the 'reduced' sporophyte features have evolved independently in each of the three clades.

ABSTRACT. Phylogenetic analyses of the Hypnales usually show the same picture of poorly resolved trees with a large number of polyphyletic taxa and low support for the few reconstructed clades. One odd clade, however, consisting of three genera that are currently treated either within the Leskeaceae (Miyabea) or Neckeraceae (Homaliadelphus and Bissetia), was retrieved in a previously published phylogeny based on chloroplast rbcL. In order to elucidate the reliability of the observed Homaliadelphus -Miyabea -Bissetia -clade (HMB-clade) and to reveal its phylogenetic relationships a molecular study based on a representative set of hypnalean taxa was performed. Sequence data from all three genomes, namely the ITS1 and 2 (nuclear), the trnS-rps4-trnT-trnL-trnF cluster (plastid), the nad5 intron (mitochondrial), were analyzed. Although the phylogenetic reconstruction of the combined data set was not fully resolved regarding the backbone it clearly indicated the polyphyletic nature of various hypnalean families, such as the Leskeaceae, Hypnaceae, Hylocomiaceae, Neckeraceae, Leptodontaceae and Anomodontaceae with respect to the included taxa. In addition the results favor the inclusion of the Leptodontaceae and Thamnobryaceae in the Neckeraceae. The maximally supported HMB-clade consisting of the three genera Homaliadelphus (2-3 species), Miyabea (3 species) and Bissetia (1 species) is resolved sister to a so far unnamed clade comprising Taxiphyllum aomoriense, Glossadelphus ogatae and Leptopterigynandrum. The well-resolved and supported HMBclade, here formally described as the Miyabeaceae, fam. nov. is additionally supported by morphological characters such as strongly incrassate, porose leaf cells, a relatively weak and diffuse costa and the presence of dwarf males. The latter are absent in the Neckeraceae and the Leskeaceae. It is essentially an East Asian family, with one species occurring in North America.

Maximum likelihood analyses based on the internal transcribed spacer region of nuclear ribosomal DNA and the chloroplast protein coding gene rps4 were conducted to investigate phylogenetic relationships among species of Plagiochila and to reconstruct the ranges of natural species groups within the genus. Based on the results of the molecular analyses and on morphological evidence, the tropical African species of Plagiochila are assigned to the sections Arrectae, Cucullatae, Hylacoetes, Rutilantes, Vagae, and the new sect. Africanae ( P. barteri, P. colorans ). With the exception of Africanae, all sections possess intercontinental ranges; their centers of diversity are in the tropics. Clade and species diversity in Africa is lower than in other parts of the tropics and may reflect drought periods of the Pleistocene. Intercontinental ranges at specific level exist between tropical America and Africa whereas similarities between tropical Asia and Africa were only recovered at the sectional level. ITS sequence sets were used to test the monophyly of species with intercontinental ranges and to explore the development of the Afro‐American range of P. boryana. A well supported clade with accessions of P. boryana from Bolivia and Uganda is nested in the robust neotropical Hylacoetes. This topology and the low genetic distance of the different P. boryana accessions provide some evidence for long‐range dispersal of P. boryana eastwards across the Atlantic, originating from the Neotropics. An African origin of the Vagae clade which includes neotropical and paleotropical taxa is suggested by the clustering of accessions from the East African Islands at the base of this clade. In addition, the presented data support the hypothesis of several switches from Africa to Asia and vice versa. A derived clade within Vagae includes accessions from the African mainland and the Neotropics. Our results seem to indicate that the extant tropical African Plagiochila flora is a mixture of old elements and rather recent immigrants.

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Recent phylogenetic analyses indicated that the backbone phylogeny of the pleurocarpous moss family Neckeraceae falls into three distinct clades. Here the detailed composition and phylogenetic relationships of the two major clades (the Neckera clade and the Thamnobryum clade) are analysed. The phylogenetic analyses, based on sequence data from the plastid rpl16 intron and the rps4-trnT-trnL-trnF cluster as well as the nuclear ITS1 and 2, retained this tripartition and revealed a strong biogeographic pattern, especially inside the Neckera clade. In addition, several morphological characters that have been held as unique and characteristic to a certain group of mosses and therefore valuable in taxonomic classification, were shown to be highly homoplastic and subjected to convergent evolution. Consequently, the circumscriptions of Leptodon and Thamnobryum are amended, the new genera Exsertotheca, Echinodiopsis and Thamnomalia (each with two species), and Alleniella (with ten species) are formally described and several implied nomenclatural changes are proposed, including synonymisation of Alsia with Neckera and Cryptoleptodon with Leptodon.

The family Neckeraceae is composed of three distinct clades, of which two, i.e. the Neckera and Thamnobryum clades, are well defined. The third clade, consisting of species belonging to Caduciella, Curvicladium, Handeliobryum, Himantocladium, Homaliodendron, Hydrocryphaea, Neckera, Neckeropsis, Pinnatella, Shevockia and Taiwanobryum, is the focus of this study. Based on sequence data from the trnS-rps4-trnT-trnL-trnF plastid cluster and the rpl16 intron as well as from nuclear ITS1&2, the phylogenetic relationships of these genera are reconstructed. The nearest relatives of this clade are resolved shedding more light on the evolution of the family. The generic composition of the clade and its individual genera are discussed; polyphyly requires redefinition of Pinnatella, Neckeropsis and Homaliodendron. The positions of Touwia and Homalia within the family are addressed in an additional analysis based on more extensive sequence data, and the corresponding new combinations are made. Several further taxonomic changes are proposed, including Circulifolium gen. nov., comprising the former Homaliodendron exiguum and H. microdendron.

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