Currently, between one-third and two-thirds of marine species may be undescribed, and previous estimates of there being well over one million marine species appear highly unlikely. More species than ever before are being described annually by an increasing number of authors. If the current trend continues, most species will be discovered this century.
AlgaeBase (http://www.algaebase.org) is a web‐searchable store of information on those protists generally considered to be algae. Access is free and some 10,000 browser searches on average now take place each month. The database was established in 1996 and at first only included seaweeds. Its main function at this time was as a catalog of the marine algae of Europe for the European Union‐funded BioMar and European Register of Marine Species (ERMS) projects, and for the recently published Atlas and Check‐list of the Seaweeds of Britain and Ireland. The data are now being extended to cover all algae. Over 50,000 names, of which about half are presently accepted species names, are now included, together with the names of some 3500 genera, about 3000 common names, approximately 700 pictures, and in excess of 28,000 literature references. URL‐based links from a number of other databases including the Species 2000 Annual Check‐list, BIOSIS, GenBank, and Codes for Australian Aquatic Biota have been implemented. It is intended to initiate similar connections from new initiatives such as EuroCat and SPICE, and a number of other global biodiversity databases. As part of a further EU‐funded project, SeaweedAfrica (http://www.seaweedafrica.org), AlgaeBase is being completely rewritten as an SQL database with a browser‐enabled interface, enabling access by a panel of taxonomic experts. AlgaeBase hopes thereby to continue to provide high‐quality access to community‐serviced data in the best traditions of the Internet.
Algae have been estimated to include anything from 30,000 to more than 1 million species. An attempt is made here to arrive at a more accurate estimate using species numbers in phyla and classes included in the on‐line taxonomic database AlgaeBase (http://www.algaebase.org). Despite uncertainties regarding what organisms should be included as algae and what a species is in the context of the various algal phyla and classes, a conservative approach results in an estimate of 72,500 algal species, names for 44,000 of which have probably been published, and 33,248 names have been processed by AlgaeBase to date (June 2012). Some published estimates of diatom numbers are of over 200,000 species, which would result in four to five diatom species for every other algal species. Concern is expressed at the decline and potential extinction of taxonomists worldwide capable of improving and completing the necessary systematic studies.
We present a consensus classification of life to embrace the more than 1.6 million species already provided by more than 3,000 taxonomists’ expert opinions in a unified and coherent, hierarchically ranked system known as the Catalogue of Life (CoL). The intent of this collaborative effort is to provide a hierarchical classification serving not only the needs of the CoL’s database providers but also the diverse public-domain user community, most of whom are familiar with the Linnaean conceptual system of ordering taxon relationships. This classification is neither phylogenetic nor evolutionary but instead represents a consensus view that accommodates taxonomic choices and practical compromises among diverse expert opinions, public usages, and conflicting evidence about the boundaries between taxa and the ranks of major taxa, including kingdoms. Certain key issues, some not fully resolved, are addressed in particular. Beyond its immediate use as a management tool for the CoL and ITIS (Integrated Taxonomic Information System), it is immediately valuable as a reference for taxonomic and biodiversity research, as a tool for societal communication, and as a classificatory “backbone” for biodiversity databases, museum collections, libraries, and textbooks. Such a modern comprehensive hierarchy has not previously existed at this level of specificity.
The concept of recreational shopper identity, a dimension of the consumer's self-concept, is contrasted with simple shopping enjoyment, which has characterized most past research on recreational shopping. Two survey studies investigate recreational shopper identity in a clothing shopping context. In Study 1, the Recreational Shopper Identity (RSI) Scale is validated with a sample of 561 adult consumers, demonstrating that recreational shopping is experienced as a true leisure activity. In Study 2, involving 354 adult consumers, the RSI Scale is used to identify three groups of shoppers who differ in the degree to which they incorporate recreational shopping into their self-concepts. Recreational shopping enthusiasts are found to engage more extensively in a range of retail shopping behaviors, to spend more money shopping (i.e., they are not just browsers), and are more “multi-channel” than other shoppers, reporting higher levels of Internet, catalog, and TV home shopping as well as traditional “brick-and-mortar” shopping.
The widespread view of taxonomy as an essentially retrogressive and outmoded science unable to cope with the current biodiversity crisis stimulated us to analyze the current status of cataloguing global algal diversity. Contrary to this largely pessimistic belief, species description rates of algae through time and trends in the number of active taxonomists, as revealed by the web resource AlgaeBase, show a much more positive picture. More species than ever before are being described by a large community of algal taxonomists. The lack of any decline in the rate at which new species and genera are described, however, is indicative of the large proportion of undiscovered diversity and bears heavily on any prediction of global algal species diversity and the time needed to catalogue it. The saturation of accumulation curves of higher taxa (family, order, and classes) on the other hand suggest that at these taxonomic levels most diversity has been discovered. This reasonably positive picture does not imply that algal taxonomy does not face serious challenges in the near future. The observed levels of cryptic diversity in algae, combined with the shift in methods used to characterize them, have resulted in a rampant uncertainty about the status of many older species. As a consequence, there is a tendency in phycology to move gradually away from traditional names to a more informal system whereby clade-, specimen- or strain-based identifiers are used to communicate biological information. Whether these informal names for species-level clades represent a temporary situation stimulated by the lag between species discovery and formal description, or an incipient alternative or parallel taxonomy, will be largely determined by how well we manage to integrate historical collections into modern taxonomic research. Additionally, there is a pressing need for a consensus about the organizational framework to manage the information about algal species names. An eventual strategy should preferably come out of an international working group that includes the various databases as well as the various phycological societies. In this strategy, phycologists should link up to major international initiatives that are currently being developed, such as the compulsory registration of taxonomic and nomenclatural acts and the introduction of Life Science Identifiers.
Klebsormidium is a cosmopolitan genus of green algae, widespread in terrestrial and freshwater habitats. The classification of Klebsormidium is entirely based on morphological characters, and very little is understood about its phylogeny at the species level. We investigated the diversity and phylogenetic relationships of Klebsormidium in urban habitats in Europe by a combination of approaches including examination of field-collected material, culture experiments conducted in many different combinations of factors, and phylogenetic analyses of the rbcL gene. Klebsormidium in European cities mainly occurs at the base of old walls, where it may produce green belts up to several meters in extent. Specimens from different cities showed a great morphological uniformity, consisting of long filaments 6-9 μm in width, with thin-walled cylindrical cells and smooth wall, devoid of false branches, H-shaped pieces, and biseriate parts. Conversely, the rbcL phylogeny showed a higher genetic diversity than expected from morphology. The strains were separated in four different clades supported by high bootstrap values and posterior probabilities. In culture, these clades differed in several characters, such as production of a superficial hydro-repellent layer, tendency to break into short fragments, and inducibility of zoosporulation. On the basis of the taxonomic information available in the literature, most strains could not be identified unambiguously at the species level. The rbcL phylogeny showed no correspondence with classification based on morphology and suggested that the identity of many species, in particular the type species K. flaccidum (kütz.) P.C. Silva, Mattox et W. H. Blackw., needs critical reassessment.
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