The estimated number of liverwort species range from 7,500 to 9,000.
Traditionally, liverworts have been subdivided into two major groups or
classes based, partially, on growth form. The class Marchantiopsida,
includes the well-known genera
Marchantia,
Monoclea,
Lunularia,
and
Riccia,
and has a complex thalloid organisation. The class Jungermanniopsida
represents an estimated 85% of liverwort species and shows an enormous
amount of morphological, anatomical and ecological diversity; plants with
leafy shoot systems are the most common growth form in this class, e.g.,
Frullania,
Jubulopsis,
Cololejeunea,
and
Radula.
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Worldwide distribution of liverworts.
Early Land Plants Today: Global Patterns of Liverwort Diversity, Distribution, and Florisitic Knowledge.
Matt von Konrat1, Lars Söderström2, Anders Hagborg1,
Matt Renner3, John Pickering4, John Engel1, & Rui-Liang Zhu5.
1Department of Botany, The Field Museum, 1400 South Lake Shore Drive, Chicago, IL 60605-2496, U.S.A. Email: mvonkonrat@fieldmuseum.org;
2Department of Biology, NTNU, N-7491 Trondheim, Norway;
3School of Biological Sciences, Heydon Laurence Building A08, University of Sydney, NSW 2006, Australia;
4517 Biological Sciences Building, University of Georgia, Athens, GA 30602-2602 U.S.A.
5Herbarium (HSNU), School of Life Science, East China Normal University,
3663 Zhong Shan North Road, Shanghai 200062, China.5
Liverworts are pivotal in our understanding of early land plant evolution.
A growing body of evidence supports liverworts as the earliest diverging lineage of embryophytes.
Liverworts form both a conspicuous and important component in many ecosystems throughout the world,
responding rapidly to environmental change, and therefore are of ecological significance in many biotic systems.
Studies of terrestrial global diversity patterns based on quantitative data have been confined to vascular plants and animals,
and more recently, macro-fungi. We here present the first preliminary data set recording the distribution of liverwort species
across 368 geo-political units based on 50,000 records from over 250 published and unpublished checklists and papers.
The data set contains over 7500 valid species names.
This figure may not be representative of the global species richness of hepatics,
however, which is possibly much lower taken into consideration the complex synonymy in many taxa,
the large number of unrevised genera and families, and the quality of the underlying data.
This database is the most comprehensive catalogue of liverwort species worldwide,
and makes significant steps toward the compilation of a worldwide checklist of liverworts.
The development of such a checklist has far reaching implications and applications,
including global mapping of species richness; comparative studies between liverwort
phytogeographic patterns with existing floristic regions and conservation hotspots
as defined by vascular plants, animals, and fungi; and assessing the state of floristic
knowledge and identifying geographical gaps in our understanding of the global liverwort flora.
Although there are many challenges ahead to obtain high quality data,
quantifying global liverwort diversity is a tractable, multi-faceted and scientifically important goal,
and everyone stands to gain by fostering this endeavour. The success of the project will lie on strong
collaborative between institutions and the bryological community in general.
- HELP NEEDED --
Matt von Konrat, at the Chicago Field Museum, and his colleagues are assembling
a team of taxonomic experts and volunteers
to catalog all liverwort species and map their geographic distribution via the web.
Discover Life, with support from the U.S. National Biological Information Infrastructure,
will provide project participants with mapping, image processing, and databasing tools
and help with technical training and support.
The project's on-line DATABASE
currently contains over 7,500 species and 50,000 geographic records.
It will be password protected for two years (until July, 2009) when it will be ready
for public consumption.
If you would like to help in this effort, please email Matt at mvonkonrat@fieldmuseum.org
or call USA-312-665-7864. For technical support and training, please email Amberlie
at dl@discoverlife.org or call USA-706-542-6676.
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Cape Horn bryophytes and liverworts
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