The genus Usnea is taxonomically revised, resulting in 43 species for Japan and Taiwan. It consists of three subgenera, Usnea, Eumitria (Stirt.) Zahlbr. and Dolichousnea Y. Ohmura, and two sections in the subgenus Usnea, Usnea and Ceratinae (Motyka) Y. Ohmura. Among the species listed in the present study, U dendritica Stirt., U hesperina Motyka, U. nidifica Taylor, U. sinensis Motyka and U. trichodeoides Vain. are reported as new to Japan and Taiwan. Usnea pygmoidea, formerly placed under the subspecies of U. confusa, is elevated to species level. The subgenus Dolichousnea is newly proposed; it is characterized by the pendent thallus, isotomic-dichotomous branching, the presence of annular-pseudocyphellae between segments, a thicker hypothecium, and a positive iodine reaction in its axis. The subgenus Usnea is separated into two sections, mainly on the basis of differences in the cortical hyphal type (leptodermatous and pachydermatous types). The morphology of soralia is found to be correlated with their origins, the type of papillae, and the occurrence of soredia and/or isidiomorphs. Annular-cracks which regularly occur between segments are separated into two categories: annular-pseudocyphellae and cracks originating in the separated cortical hyphae. Cortical tissues are found to be one of four types which are fiorida-, merrillii-, ceratina-, or baileyi-types. The specificity of lichen substances to species is recognized. Twenty-four species show no chemical variation, while 19 species have two or three (rarely four) chemical races within a species.

  Based on multi-character analyses of selected species the Thuidiaceae are redefined, and a realignment is presented of the species previously accommodated in Thuidium s. amplo (Thuidium Schimp. sensu Brotherus 1925, Thuidiopsis (Broth.) M.Fleisch., and Pelekium Mitt.), based on a similar analysis of numerous well-known species and additional information from many remaining ones. The family is characterized by a large combination of character states shared by all genera: regularly pinnate ramification; scattered paraphyllia; mostly cordate or triangular, acute to long-acuminate, plicate stem leaves with recurved margins often bearing paraphylloid appendages below; single, strong, often almost percurrent and almost always distally rough costae bearing paraphylloid or pseudoparaphylloid appendages near insertion; narrow, both mammillose and papillose median leaf cells (mostly ornamented at both leaf faces); weakly differentiated basal and apical leaf cells; undifferentiated or poorly defined alar cell groups consisting of cells shorter than the adjacent leaf cells, if differentiated; leaves of ultimate branches markedly different from stem leaves in bipinnate or tripinnate species; tubular perichaetia with inner leaves ending in a straight, flexuose, or twisted acumen; ovoid to cylindrical, inclined capsules (except in many specialized epiphytes); rarely distinctly collenchymatous exothecial cells; superficial stomata; a hypnoid peristome; and almost always cucullate, naked, smooth calyptrae. Included are Abietinella, Actinothuidium, Boulaya, Bryochenea, Bryonoguchia, Echinophyllum, Haplocladium, Helodium, Hylocomiopsis, Orthothuidium, Pelekium, Rauiella, Thuidiopsis, Thuidium, Aequatoriella gen. nov. (type: Thuidium bifarium Bosch & Sande Lac.), and Indothuidium gen. nov. (type: Thuidium kiasense R.S.Williams). Pelekium sensu Brotherus is judged polyphyletic. Pelekium s.str., consisting of the type species (P. velatum) is lumped with Cyrto-hypnum (Thuidium subg. Thuidiella), for which Pelekium is the older name. Inouethuidium is excluded. The genera are briefly discussed. In Appendix I the 2 new genera, Thuidium pseudoglaucinum sp. nov., Bryochenea vestitissima (Besch.) Touw, comb. nov., and 28 new combinations in Pelekium are validated, and heterotypic synonyms are proposed relating to American, European, and Madeiran species. The American Pelekium muricatulum (Hampe) Touw (earlier lumped with Pelekium minutulum) is reinstated.

  This paper tabulates the valid species names of Hookeriaceae reported for Australia together with synonyms reported for Australia, species new to science, new to Australia, new combinations and those names rejected from the Australian moss flora. Australian and overseas distribution of the species is discussed, as well as ecology and sub-strate preferences of the species is also summarised. Altitude-latitude graphs are also presented and discussed.

  Circumscription of the family Sematophyllaceae is controversial, and taxonomic position of the genera Brotherella, Trismegistia, Wijkia and its allies has been repeatedly discussed and is still fluctuating. A phylogenetic study was carried out to investigate the phylogenetic position of the genera Brotherella, Trismegistia, Wijkia and their allies inferred from the chloroplast ribulose 1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene data. The relationships between 40 species representing the Sematophyllaceae and related taxa are evaluated based on the rbcL data set using the following methods: neighbor-joining (NJ), minimum-evolution (ME), maximum-parsimony (MP) and maximum-likelihood (ML) methods. The results of the present study suggest that (1) the family Sematophyllaceae (s. lat.) are monophyletic; (2) the genera Wijkia, Trismegistia and Acanthorrhynchium do not form a single clade; and (3) the genera Brotherella, Pylaisiadelpha, Heterophyllium, Isocladiella, and some species treated as members of the Hypnaceae, such as Hypnum tristo-viride or Isopterygium tenerum should be placed in the Sematophyllaceae (s. lat.). Our research shows that the Sematophyllaceae (sensu Hedenäs & Buck 1999) are not monophyletic. Since the monophyly of the Sematophyllaceae (s. lat.) including Brotherella and its allies is well supported, we propose here that we could treat the family in a wider sense. Furthermore, the present study suggests that Entodontaceae (s. str.) are resolved as a monophyletic group, and should be placed in a clade sister to the Sematophyllaceae (s. lat.). The results show the necessity to reconsider the familial circumscription of the Sematophyllaceae and the Hypnaceae.

  Heteroscyphus mononuculus Engel, a new member of the Geocalycaceae, is described and illustrated from New Zealand.

  A total of 34 species of hepatices were collected from various sites of Hong Kong. Extracts of these species are screened for antimicrobial activity, and 28 species showed repeatable biological activity warranting further investigation. From the 95% ethanolic extract of Plagiochila sciophila Nees, guided by bioactivity-directed isolation, a new cyclic bis(bibenzyl) derivative named isoriccardin C1'-monomethyl ether (1) and the previously known diterpene dialdehyde perrottetianal A (3) were isolated.

  South America with half of all the known species represents most probably the primary diversity centre of the ascolocular lichen family Roccellaceae (Arthoniales). Nevertheless, neither a modern identification key nor a topical survey are available for the biologically, ecologically and phylogenetically interesting taxa occurring on the mainland and (or) the adjacent islands. A computeraided, dichotomous key has therefore been prepared, based as far as possible on easily detectable characters. All 51 species considered, belonging to 11 genera, are endemics. An appendix comprises nomenclatural, taxonomical and biogeographical additions, corrections and remarks. Among other items these embody diagnoses and descriptions of four new species: Roccella colonii Follm. sp. nov. (Galápagos Islands), R. humboldtiana Follm. sp. nov. (Northwestern Neotropics), R. transludica Follm. & B. Wern. sp. nov. (Galápagos Islands), Roccellina corrugata Follm. sp. nov. (North Chile). Dirina paradoxa f. sorediata Tehl. (North Perú) and Roccellina cerebriformis f. sorediata Tehl. (Central Chile to Central Perú) are reduced to the synonymy of the corresponding typical species. In addition, the genus name Protoroccella Follm. is emended and validated with P. minima (Sant.) Follm. comb. nov. as generic type and P. follmannii (Sánch.-Pinto & M. Schulz) Follm. comb. nov. (both North Chile). At present, Camanchaca corallina Follm. & Peine, Protoroccella minima (Sant.) Follm. (both North Chile) and Roccella gayana Mont. (Central and South Chile) have to be regarded as seriously endangered taxa, whereas R. babingtonii Mont., R. fragillima (Darb.) Follm. (both Central Chile) and R. nigerrima (Darb.) Follm. (Galápagos Islands) obviously became extinct within the respective areas of distribution in recent times.

  Based on recent acquisitions of the Australian National Herbarium since 1982, mainly the collections of J.A.Elix and H.Streimann, new distribution data are presented for 162 species. This includes 31 species new to Australia: Acarospora reagens, Collema fragrans, Cyphelium australe, Dictyonema ligulatum, Dimerella pineti, Diploschistes farinosus, D. gyrophoricus, Dirinaria complicata, Heterodermia isidiophora, Hyperphyscia pruinosa, Megalospora atrorubicans ssp. atrorubicans, Myriotrema bahianum, M. compunctum, M. terebratulum, Ocellularia aurata, O. berkeleyana, Ochrolechia africana, Opegrapha filicina, O. phylloporinae, Peltula marginata, Physcia dimidiata, Porina sphaerocephala, Porpidia cinereoatra, Pyrenula corticata, Pyxine cylindrica, Thelotrema platysporum, Thyrea confusa, Trapelia involuta, Trichothelium triseptatum, Trypethelium aeneum, Umbilicaria nylanderiana. Most of these are tropical taxa, found in Queensland. The other species are newly recorded for one or more Australian states.

  The effect of habitat conditions on the size and number of phycobiont cells, on the content of chlorophylls and carotenoids in the thalli of Cetraria islandiea, Cladina arbuscula, Hypogymnia physodes, Parmelia sulcata and Peltigera rufescens were investigated. Seasonal differences were found in the size of phycobiont cells. The mean size of algal cells increases from February to October, the smallest were observed in the winter. Lichen species collected from the sites distant from town were characterised by the largest number of phycobiont cells and the highest percentage of live cells, hence the high content of photosynthetic pigments. Seasonal differences were observed in chlorophyll content in lichen thalli. The highest pigment concentration was found in thalli collected in the winter and spring, the lowest were noted in the summer.

  Halophilic or salt tolerant lichen mycobionts were screened for 77 species on an NaCl enriched medium. Only the Niebla homalea mycobiont collected from the North American Pacific seashore showed evident halophilic growth: 145% growth on malt-yeast extract agar-medium supplemented with 0.9 M NaCl and 129% growth at 1.2 M NaCl in comparison with that of the zero NaCl medium. In addition, mycobionts of Arthonia cinnabarina, Chaenotheca brunneola, Caloplaca scopularis, Ramalina subbreviuscula and Vermilacinia combeoides harvested from seashore showed relatively better growth on NaCl enriched medium; however, some mycobionts are sensitive to salt. These selected mycobionts were also tolerant to KCl and glycerol added.