Haplomitriopsida

Abstract: Some biogeographical features of bryophytes associated with subtropical-temperate ecosystems in Chile are examined, including diversity, concentration of species richness, endemism, biogeographical composition and disjunctions. The historical-biogeographical interpretation of these characteristics considers the major evolutionary changes of the group in three different temporal scenarios, according to geological, paleobotanical and molecular evidences. First, simple- and complex-thalloids liverworts represented in Chile are examined, belonging to the Classes Haplomitriopsida and Marchantiopsida- Marchantiidae, archaic lineages linked to the pre-Cenozoic colonization of the Pangea mega-continent. Examples of simple-thalloids liverworts of Class Jungermanniopsida-Pelliidae, hornworts of the Class Anthocerotopsida and mosses of the Classes Bryopsida and Polytrichopsida illustrate the paleo-austral distribution patterns of bryophytes from the temperate region of Chile, related to the Gondwana breakup and expansion of Angiosperms during the Cretaceous/Paleogene. A second scenario, considers the final uplift of the Andes and the development of the Arid Diagonal of South America during the Neogene, processes that have played a major role in the biogeographical structure of the Chilean and South American floras. In this context, leafy liverworts associated with the relict forests of the Chilean semi- arid coast stand out, particularly epiphyllous liverworts of the two most diverse families of the Class Jungermanniopsida-Jungermanniidae, Lejeuneaceae and Plagiochilaceae, adapted to microclimates favored by coastal fogs. The last scenario discusses the significant role of the Pleistocene glacial cycles in the expansion of the sub-Antarctic temperate-cold element throughout central-southern Chile, and its effects on the concentration of bryophyte richness associated with Chile’s temperate-rain ecosystems.

Abstract: The Marchantiophyta (liverworts) includes three classes, the Haplomitriopsida, Marchantiopsida and Jungermanniopsida, and 15 orders, 82 families, 316 genera (Table 1.1), and 6,000 species. These small plant groups are distributed nearly everywhere in the world. New species are still being recorded in literature. There are 54 endemic genera in countries of the southern hemisphere, such as New Zealand and Argentina, as shown in Fig. 2.1 (364). In Asia including Japan, a relatively large number of endemic genera (21) has been recorded, but Europe, North America, and Africa including Madagascar are quite poor regions for endemic genera. The richness of the endemic genera of bryophytes in southern hemisphere suggests that the bryophytes might originate in the past from what is now Antarctica some 350,000,000 years ago and then they were introduced to the northern hemisphere during a long range evolutionary process. In Japan, Yaku Island is considered an important place to locate bryophyte species. In the southern hemisphere, New Zealand is one of the best countries to observe many different species of the Marchantiophyta, which are totally different from those found in Japan.

Abstract: Mutually beneficial associations between plants and soil fungi, mycorrhizas, are one of the most important terrestrial symbioses. These partnerships are thought to have propelled plant terrestrialisation some 500 million years ago and today they play major roles in ecosystem functioning. It has long been known that bryophytes harbour, in their living tissues, fungal symbionts, recently identified as belonging to the three mycorrhizal fungal lineages Glomeromycotina, Ascomycota and Basidiomycota. Latest advances in understanding of fungal associations in bryophytes have been largely driven by the discovery, nearly a decade ago, that early divergent liverwort clades, including the most basal Haplomitriopsida, and some hornworts, engage with a wider repertoire of fungal symbionts than previously thought, including endogonaceous members of the ancient sub-phylum Mucoromycotina. Subsequent global molecular and cytological studies have revealed that Mucoromycotina symbionts, alongside Glomeromycotina, are widespread in both complex and simple thalloid liverworts and throughout hornworts, with physiological studies confirming that, in liverworts at least, these associations are mycorrhizal-like, and highlighting important functional differences between Mucoromycotina and Glomeromycotina symbioses. Whether a more prominent role of Mucoromycotina symbionts in plant nitrogen nutrition, as identified in liverworts, extends to other plant lineages, including the flowering plants, is a major topic for future research. The latest finding that ascomycete symbionts of leafy liverworts are not restricted to one fungus, Rhizoscyphus ericae, but include species in the genus Meliniomyces, as shown here in Mylia anomala, together with the recent demonstration that R. ericae forms nutritional mutualisms with the rhizoids of Cephalozia bicuspidata, fill other major gaps in our growing knowledge of fungal associations across land plants.