SPECIES ACCOUNTS

Time 2020-10-18 13:04:48

Web Name: SPECIES ACCOUNTS

WebSite: http://www.speciesaccounts.org

ID:86065

Keywords:

SPECIES,ACCOUNTS,

Description:

This website aims to list and count the known extant speciesof the world grouped by how they are related to one another through evolution.The Species Accounts website is a work in progress. Currently, about 11.0% ofdescribed extant species are listed and the remainder have their place held asdescribed below in the Introduction. Contact us for moreinformation.Contributors: Christine Metlen, B.F.A. (Amphibia, Anura, Squamata, Sauria, Serpentes) Photography: Joel Metlen, B.F.A.Web Page Design: Elizabeth Ann Sullivan, B.A., M.A.INTRODUCTIONLearn about the definitions and methods used for the SpeciesAccount website.SPECIES LISTSGo directly to the list of species organized by group.INTERNET LINKSBOOKS AND ARTICLESINTRODUCTIONThis phylogenetic list of described extant species of theworld is called SPECIES ACCOUNTS because its purpose is to list and count thenumber of species in each group known to be related to each other throughevolution.The definition of species used is the most liberal andrelies on the species definition used by experts in the study of each taxonomicgroup of organisms. In birds, species are usually clearly delineated bybreeding groups. In some corals, which exhibit extensive hybridizationand a reticular rather than dichotomous pattern of evolution, speciesdefinition may be one of convenience. In such cases, species may have tobe defined by relying on recognizable groupings of physical, functional orother traits, while realizing that species so defined may exist along aseamless cline of organisms. Species definition is particularly difficultwith viruses and bacteria.Only described species are listed. Experts in sometaxa estimate that the actual number of species existing today may in somecases be up to 1000 times as many as those described.This is a phylogenetic list, not a classification. Thenames used of species, genus, family or higher grouping rely on the opinions ofexperts in each taxonomic group. Species are grouped, listed and countedsolely on the basis of their closest relationships in evolution regardless oftheir formal classification. The structure of the list therefore takesthe form of a family tree with each species shown in relation to its closestrelatives.Among the over 1 million described extant species the detailedrelationships in evolution are seldom fully known. Several rules aretherefore used in preparing this list. One would like to insure that eachgroup of species listed was monophyletic at each level of the familytree. For a group to be monophyletic, two conditions must be met:first, all species in the group must have evolved from one single ancestor;second, all descendants of that ancestor must be represented in thegroup. If either criterion is not met, the group is considered a paraphyleticgroup. When considering the evolutionary relationships among allknown species, the second criterion is seldom met since the relationships ofmany species are not precisely known. For this reason this list requiresthat the first criteria be met, that is, that all species in a group descendedfrom a single ancestor, but allows the possibility that other species or groupsseparately listed may actually belong in that group.The most conservative opinion accepted by most experts in agiven taxon is used. In this way error is minimized. A newlydescribed species or group, if its relationships were not known, would beplaced by itself at the lowest branch on the tree where knowledge of itsevolutionary relationships was certain. With further knowledge thisbranch would be moved further up the tree to its proper place. This convention might be summarized as ‘errors toward thebase of the tree’. An example is the placement of the coelacanth,Latimeria chalumnae. Latimeria is currently placed at the base of thebranch containing all the Jawed Vertebrates until such time as its positionfurther up the tree is understood.The position of a species or group at the base of the treeor at a ‘low branch’ does not necessarily imply early separation from othergroups in evolutionary time but may mean that its relationships are not moreclearly defined. An example of this is the various groups of viruseswhich are placed at the base of the tree.SPECIES ACCOUNTS is a work in progress. When a speciesname is not yet available, its place on the list is held in one of twoways. In a short list, the species may be given a temporary number.An example is the genus Theligonum which contains 3 species. Theligonumcynocrambe is named and space is held for the other 2 as ‘Theligonum 2’, ‘Theligonum 3’. In longer lists, space is heldby using the word ‘Other’ before the group name. The genus Digitaliscontains 19 species. Digitalis lanata is named and space is held for theother 18 as ‘18 Other Digitalis’.Currently, about 11.0% ofdescribed extant species are listed and the remainder have their place held asdescribed above. Help with this project is welcomed. Click here to go directly to: SPECIES LISTSCONTACT USPlease send comments, corrections, or lists of names to beincluded by regular mail to: Stephen Gene Sullivan, Ph.D., M.D., 533 East 13thStreet, New York, NY 10009, USA.SELECTED REFERENCESINTERNET LINKS:THE TREE OFLIFE HOME PAGESPECIES 2000 HOME PAGEGLOBALBIODIVERSITY INFORMATION FACILITYDISCOVER LIFEENCYCLOPEDIA OF LIFENATIONALCENTER FOR BIOTECHNOLOGY INFORMATION TAXONOMY BROWSERLIST OFBACTERIAL NAMES WITH STANDING IN NOMENCLATURETHE INTERNATIONAL PLANT NAMESINDEXANGIOSPERMPHYLOGENY WEBSITEINTERNATIONAL LEGUMEDATABASE INFORMATION SERVICEPHYLUM CTENOPHORA:LIST OF ALL VALID SPECIES NAMESTHEWORLD SPIDER CATALOGTHEDIPTERA SITEASILIDAEHOMEPAGETRICHOPTERAWORLD CHECKLISTHYMENOPTERAON-LINE DATABASEAPRELIMINARY CHECKLIST OF THE FLAT BARK BEETLES OF THE WORLDDR.BILLIE J. SWALLA (Deuterostomia and Tunicata)CHRISCAMERON’S HOME PAGE (Hemichordata)FISHBASEAMPHIBIAWEBLIVINGUNDERWORLD- AMPHIBIAN INFORMATION RESOURCETHE EMBL REPTILEDATABASEBOOKS AND ARTICLES:VIRUS TAXONOMY. CLASSIFICATION AND NOMENCLATURE OFVIRUSES. SEVENTH REPORT OF THE INTERNATIONAL COMMITTEE ON TAXONOMY OFVIRUSES. M. H. V. van Regenmortel, C. M. Fauquet, D. H. L. Bishop,Eds. Academic Press, San Diego, 2000.FIVE KINGDOMS. AN ILLUSTRATED GUIDE TO THE PHYLA OFLIFE ON EARTH. Second Edition. L. Margulis and K. V.Schwartz. W. H. Freeman, New York, 1988.BERGEY’S MANUAL OF DETERMINATIVE BACTERIOLOGY. NinthEdition. J. G. Holt, N. R. Krieg, P. H. A. Sneath, J. T. Staley, S. T.Williams. Williams and Wilkins, Baltimore, 1994.HANDBOOK OF PROTOCTISTA. L. Margulis, J. O. Corliss,M. Melkonian, D. J. Chapman, Eds. Jones and Bartlett, Boston, 1990.THE EVOLUTION AND CLASSIFICATION OF FLOWERING PLANTS.Second Edition. A. Cronquist. The New York Botanical Garden, Bronx,1988.THE PLANT-BOOK. A PORTABLE DICTIONARY OF THE HIGHERPLANTS. D. J. Mabberley. Cambridge University Press, Avon, 1987.AINSWORTH AND BISBY’S DICTIONARY OF THE FUNGI. EighthEdition. D. L. Hawksworth, P. M. Kirk, B. C. Sutton, D. N. Pegler.CAB International, Oxon, 1995.GRZIMEK’S ANIMAL LIFE ENCYCLOPEDIA. VOL. 1.LOWER ANIMALS. H. C. B. Grzimek, Ed. Van Nostrand Reinhold, NewYork, 1972.GRZIMEK’S ANIMAL LIFE ENCYCLOPEDIA. VOL. 3.MOLLUSKS AND ECHINODERMS. H. C. B. Grzimek, Ed. Van NostrandReinhold, New York, 1972.IMM’S GENERAL TEXTBOOK OF ENTOMOLOGY. TenthEdition. 2 Vols. O. W. Richards and R. G. Davies. John Wiley,London, 1977.A WORLD CATALOGUE OF FAMILIES AND GENERA OF CURCULIONOIDEA(INSECTA: COLEOPTERA) (EXCEPTING SCOLYTIDAE AND PLATYPODIDAE). M. A.Alonso-Zarazaga and C. H. C. Lyal. Entomopraxis, Barcelona, 1999.THE PHYLOGENY AND HIGHER CLASSIFICATION OF THE STAPHYLINIDAEAND THEIR ALLIED GROUPS (COLEOPTERA, STAPHYLINOIDEA). Shun-IchiroNaomi. ESAKIA (23): 1-27, 1985.MOLECULAR PHYLOGENY OF THE PROTOCHORDATES: CHORDATEEVOLUTION. L. Zeng and B. J. Swalla. CAN. J. ZOOL. (83): 24-33,2005.FISHES OF THE WORLD. Third Edition. J. S. Nelson.John Wiley, New York, 1994.WALKER’S MAMMALS OF THE WORLD. Sixth Edition. 2Vols. R. M. Nowak. Johns Hopkins University Press, Baltimore, 1999.

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