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BZN Volume 62, Part 4, 16 December 2005

General Articles & Nomenclatural Notes


General Articles and Nomenclatural Notes with the following titles were published on 16 December 2005 in Volume 62, Part 4 of the Bulletin of Zoological Nomenclature

Copies of these General Articles and Nomenclatural Notes can be obtained free of charge from the Executive Secretary, The International Commission on Zoological Nomenclature, c/o The Natural History Museum, Cromwell Road, London SW7 5BD, U.K. (e-mail: iczn@nhm.ac.uk).


General Article

Nomenclature of Higher Taxa: a new approach

M.A. Alonso-Zarazaga
Depto. de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias
Naturales, José Gutiérrez Abascal 2, E-28006 Madrid, Spain
(e-mail: mcnaz39@mncn.csic.es)

Abstract. In the 21st century, Zoology faces many challenges. One of these is the preparation of a Code of Nomenclature that can both meet the new needs of zoologists and fill gaps in the present wording and coverage. One of these gaps concerns the nomenclature of higher taxa. After a discussion of the problems, it is proposed that the new Code should regulate names above the family-group, usually known as phylum-, class- and order-group names, and that non-typified names should be discarded gradually. A logical set of standardized connectors and endings is proposed for use in a single, ‘expanded’ family-group, renamed as the ‘upper uninominal group’. This group would be typified by the names in the immediately inferior group (the genus-group) as is standard in the present Code. This way, the internal logic of the Principle of Typification is maintained. Different problems that may occur are identified and solutions proposed.

Introduction
  The nomenclature of taxa above the family-group was a matter of debate even before the Règles of 1905 were published. A short historical and formal analysis of the problem was presented by Starobogatov (1984) in Russian and a more recent English translation (Starobogatov, 1991). He also reviewed the problems that implementation of a typified system for these names would face, discussed the advantages of such implementation and proposed a ‘Draft of recommendations for the regulation of the nomenclature of taxa of rank higher than superfamily’ with 40 points.
  The aim of the present paper is to identify shortcomings in Starobogatov’s proposal and to propose more pragmatic and Code-compliant solutions. Among the remaining problems one of the most important is that the Code does not regulate nomenclature of taxa above superfamily. This extension of coverage, seemingly, has not been undertaken for fear of the ‘serious breakdown in existing customs concerning the formation and utilization of names of higher categories’
(Starobogatov, 1991).
  However, a more serious problem is found when the number of these taxon names will increase with the future discovery and description of the millions of species thought to be still unknown, and the need for new higher categories to rank them. Examples include the recent description of a new phylum, Cycliophora Funch & Kristensen, 1995, or a new order of insects, Mantophasmatodea Zompro, Klass, Kristensen & Adis, 2002.
  Phylogenetic analysis is also playing an important role in this multiplication of names. Some authors want a name for every node or branch of a given phylogenetic tree, no matter which analytic tool has been used for its construction. I consider this unnecessary, but I believe the Code must give exact rules for zoologists requiring names under the Linnaean binominal system. Other nomenclatural systems for
phylogenetic systematics have been devised, some based on a very strict mathematical analysis of tree topology and hierarchy topology (Papavero et al., 2001). Current Linnaean nomenclature can deal adequately with the naming of phylogenetic tree-based taxa. Other systems are contrary to the Principles of the Code and will not be referred to here.
  Names above the superfamily level belong, according to Starobogatov (1991), to two categories: typified and descriptive, the first being those linked by their spelling to an included genus-group taxon, the second those based on one or several features of the included organisms. A more complex approach to the attributes of the taxa can
be found in Kluge’s works (e.g. Kluge, 1996 in Russian, 1999 in Spanish and English), where a different structure of names of taxa is proposed. However, most of the inherent complexity affects only non-typified taxon names, for which the descriptive term may be taken in different senses depending upon the contents of their taxa, and for these I will use the term ‘non-typified’. This is the only difference that affects the establishment of the rules of the Code, which is covered by the Principle of Typification.
  In the following description, the term ‘high-level names’ encompasses the main categories (in Latin) phylum, classis and ordo, and the intermediate ranks that can be obtained exclusively by the use of the prefixes super-, sub-, infra- and parv(i)-. No name related to the category ‘kingdom’ is intended. The category ‘cohors’ as a part of the order-group should be avoided because it has been used previously at other ranks. The term ‘low-level’ will be used to encompass uninomina of the family- and genus-groups.

Homonymy and hemihomonymy
  Two problems are inherent in the absence of nomenclatural rules for high level taxa. One is homonymy — two names in use are well known for being homonyms: Decapoda Dujardin, 1834 in Mollusca, and Decapoda Latreille, 1803 in Crustacea. Both are or have been in use at the same time, because the Principle of Priority contained in the Code does not apply to these names. If it did, only Decapoda Latreille, 1803 would be available. The number of names falling in this category is probably high, although I have not done any research to count them, since their number is irrelevant to the argument I present here. As envisaged in the present Code, homonymy is to be avoided because of the confusion it brings to scientific communication.
  Hemihomonymy is a peculiar situation, described by Starobogatov (1991). This happens when a high-level uninomen and a low-level uninomen are identical, even when the high-level uninomen is not typified by a similarly spelt genus-level name. This conflict is already present between some family-group names and some genus-level names ending in –ina, and perhaps in some ending in –oidea. This is a particular feature stemming from the use of some Latin endings, which, as –a, can be both singular feminines or plural neuters. However, atypical generic endings in –ae or in –i could also be included in this because of the possible risks incurred (see table 1).
  Starobogatov (1991) identified both the problems mentioned above as the main sources of nomenclatural problems that could be solved by the introduction of typified high-level names. I think that typified high-level names will solve many other present-day problems, as it is the uncontrolled proliferation of names linked to different taxonomic concepts in phylogenetic trees, or a change of meaning for nominal taxa introduced by subsequent authors. An in-depth explanation of this
issue is to be found in Kluge’s (1996, 1999) criticism on the myth of the polyphyly of Hexapoda, a matter complicated by misunderstandings of meanings and ranks of non-typified taxa.

Table 1

Standard endings in high-level taxa names
  Starobogatov (1991) discussed earlier systems of standardization of name endings for high-level taxa names. He pointed out that a logical development would be to exclude any endings which would lead to homonymic or hemihomonymic identity. He provided a partial check of endings likely to lead to intergroup homonymies.
  I present here an analysis of genus-group endings based on the recent availability of Neave’s Nomenclator Zoologicus in electronic format as a database (http://uio.mbl.edu/NomenclatorZoologicus/). For this analysis (table 2) I differentiate between endings and connectors, from a philological point of view. I consider endings to be in this case the last 1–2 letters (two vowels or vowel plus s) or in a single case the last 3 letters (-ees) of a name. Connectors are the letters linking the stem of the type genus to these endings, e.g. in the family name RANIDAE, the stem would be ran- (from genus Rana), the connector –id- and the ending –ae (a first declension nominative plural). Latin plural endings and their gender and declension are shown in table 1.

Table 2. Ending presence and connector use in genus-group names in Zoology

  Connectors have been selected from those present on tables 1–3 in Starobogatov (1991), plus the mandatory ones for family-group names in the Code. I have added most of the commonly used connectors in typified names in Zoology after a survey of Parker (1982), and of Sibley et al. (1988) for Aves.
  One of the most striking points is the fact that the –a ending has been used with almost every conceivable connector as part of generic names (in fact about 50% of the generic names in zoology end in this letter). This makes a strong reason for avoiding this ending as a part of any high-level name. Unfortunately, we already have the combination connector+ending in –ina mandatory for subtribes, a combination to be
found in 9,062 generic names, and similarly the combination –oidea for superfamilies, found in 281 generic names. To distinguish between both kinds of name, the italicisation of suprageneric names should be formally prohibited. Another ending to be discarded is –us (possible confusion with 2nd declension masculine nominative singular names, representing more than 25% of generic names). The ending –es could also fall into the same category, and is discussed in combination with the connectors.
  Other duplicated occurrences of combinations of connector+ending between zoological genera and non-zoological categories are shown in the legend to table 2.
  From table 2, it can be deduced that several types of ending are rare in other low-level taxon names, and thus are desirable as endings for the high-level taxa in order to establish a difference. These are: -ii (0 hits), -oi (1), -ei (11), -ees (11), -i (168).
  Regarding connectors, table 2 gives also some that could be used in combination with these endings: -inac- (1), -ozoid- (1), -ariin- (2), -ionin- (12), -omorphin- (19), -oidin- (20), -iodin- (21), -ozo- (24), -inin- (40), -iform- (43), -oil- (49), -icin- (57), -ace- (59), -oin- (70). From these, those finishing in -in- can be discarded inmediately, since their combination with an –i ending would give the same ending –ini in use for tribes. This leaves –inac-, -ozoid-, -ozo-, -iform-, -oil- and –ace. I would suggest another possible ending, -omorph-, that is found as a part of generic names only in combination with endings –a, –ia, and –us, endings to be discarded from high-level names. A similar situation should be considered in evaluating the ending –es, which, although present in 24,647 genera, is never present in the combinations –inaces, -ozodes, -ozoes, -iformes, -acees and –omorphes, and only once as –oiles. I do not follow Rasnitsyn’s (1992) recommendation of avoiding this ending.
  If a system of endings is to be constructed with these connectors and endings, my view is that simple rules should be followed, ascribing a particular ending to every rank and a particular connector to every group, as intended by Starobogatov (1991). Thus, a combination of connectors (1 or 2) and a single ending will immediately indicate the rank of the nominal taxon. Secondary connectors are needed because of the scarcity of available, unmistakably different endings. Starobogatov’s proposal results in a somewhat confused assignment of endings and connectors. For the phylum-group (which in his case includes as a rank the division, not considered here) he uses consistently the connector –ozo- or combinations of this and another connector (for example, -ace-); only the ending –ozoides has one hit as ending for a genus. For the class-group, he uses different connectors (-id-, -iod-, -ion-) and endings; of the resulting combinations, the one selected for the class (-iodes) has 438 hits as a genus ending and should be discarded. For the order-group, the connectors –omorph-, -iform-, -oid- and –oin- are used; hits are 0 or 1 for the combinations.
  In my opinion, Starobogatov’s system cannot be followed because of its lack of formal logic. My proposal is to use three well known connectors (already in use in some zoological taxa), each for one of the three levels (phylum-group, class-group, and order-group): respectively, -ozo-, -omorph- and –iform-. These will be combined with five mandatory endings for ranks as shown in table 3. Endings have been selected to avoid changes in some populated groups, such as fish, where they are in common use. The logical reasons for the endings are as follows: the first three (super-, (no prefix) and sub-) are simple and in alphabetical order: -ae, -es, -i; the last two (which are also less likely to be needed) have a secondary connector in alphabetical order (-ace- for infra-, -id- for parv(i)-), keeping the same preferred ending (-i). These two connectors are already in use in Zoology. If there is the belief that more ranks would be needed, the Commission could rule on the same logical basis. Taxon names ending in –ae will be first declension plural feminine substantives, while those ending in –es and –i will be respectively third parisyllabic and second declension plural masculine substantives.
  It is evident that this proposal is innovative and departs in several points from customary nomenclatural usage in some groups. However, as I have said in the introduction to this paper, the time is right to face such problems, in order to achieve uniform nomenclatural procedures in all animal taxa.

Table 3. Proposal of mandatory combinations (connector(s) + ending) for groups and ranks in Zoology.

Table 3

Structure of levels and typification
  The above-mentioned statements are based on Starobogatov’s acceptance of Rohdendorf’s (1977) proposal to keep three different groups of names: phylumgroup, class-group and order-group. The Principle of Coordination should apply to these three groups. Starobogatov differentiated the ‘total coordination’ proposal inherent in Rohdendorf’s treatment (where all uninominal high-level names are merged with the family-group names) from his own, which considers the existence of these three groups as separate entities with separate internal coordination.
  Even if Starobogatov’s proposal is not accepted (and I will present strong reasons not to do so) the formal nomenclatural proposal here presented could be maintained, based on sound logical ground.
  Rohdendorf’s proposal was rejected on the principle that ‘in doing so, the quantity of names, authors and dates does not grow very much, and the nomenclatural stability of higher-rank taxa is secured more dependably . . . and the names of higher taxa are based primarily on the best known and characteristic genera’. This concern is basic for a system that attempts to incorporate all available names. This would not
be an onerous task. He went on: ‘In so doing, the name of a taxon may be formed from any available generic name regardless of which family-group name was published earliest’. This statement is the weakest point in Starobogatov’s system, since the level at which to seek a type-bearing taxon for all high-level taxa should be the genus-group, ignoring the family-group names. This procedure is directly contrary to the Principle of Typification, and would render any Code established on such a procedure deeply illogical.
  A ‘three-group system of coordination’, as Starobogatov called it, cannot be allowed to undermine the Principle of Typification. In Starobogatov’s concept, the three groups (phylum-, class- and order-groups) would be typified in any included genus whose name was used to typify any high-level taxon name (that is, the family-group names would be discarded). If we strictly follow the rationale of the Code, a phylum-group name should be typified with the oldest available class-group name, this in the oldest available order-group name, and the latter in the oldest family-group name (with the appropriate ending changes).
  Starobogatov states: ‘With a three-group system of coordination, we can calmly consider names of the order-group and the family-group, even ones based on the same genus, as originating independently, and to ascribe to them different authors and dates of publication’. This is, plainly, not desirable. This procedure would add to the thousands of uninomina already in use for family-group names, many others with different authors and dates (which would be found in the older literature), and, what is worse, much more debate on precedences, with the consequent requests to the Commission.
  According to this, it would seem that we would then have to decide whether we consider high-level taxa divided into a ‘three-group system of coordination’ as Starobogatov (1991) proposed (with a stairway typification system, not with his typification directly to genus for each level), or whether we consider them to be a ‘single-group system of coordination’ (Rohdendorf, 1977). In any case, the unique type-bearing taxon should be sought in the family-group.
  Instead, I am proposing here that we be pragmatic and use what we already have. In the current (4th Edition) Code, we already have a uninominal level in use and well established: the family-group names. This group has names already typified in genera, and because time, and consequently Priority, is the main criterion, the oldest family-group names are usually based on the oldest (or at least the best known) generic names. I propose here simply to expand the family-group to include all the uninominal names above the genus-group, to be called the ‘upper uninominal group’.
  In this system, phylum-group, class-group, order-group and family-group would each become a subgroup. Only names given in the family-subgroup would be available for nomenclatural purposes. In the family-subgroup, they would keep author and date as a complementary attribute, but author would not be necessary for taxa above the family-subgroup. Names in the phylum-, class- and order-subgroup would have date only, in order to determine their priority. Typified names given for a taxon in a rank above the family-subgroup would not be available.

The new groups of names
  According to the above proposal, the zoological categories would be gathered into three different groups (or coordination levels):
  The ‘upper uninominal group’. Its defining characters being plural substantive uninomina that never unite to the specific epithet to form a name, typified on a genus group name, formed by its stem and a set of connectors and endings. To be written in plain fonts.
  The ‘genus group’ (‘lower uninominal group’). Its defining characters being singular substantive uninomina that may unite to the specific epithet to form names of the ‘species group’, typified on a species group name. To be written in a different font from the rest of the text, usually italics.
  The ‘species group’. Its defining characters being binomina or trinomina, typified on specimens (extant or not). To be written in a different font from the rest of the text, usually italics.

Transition from contemporary nomenclature
  This ruling would alter only minimally the usual names of many taxa. In some cases, just one or two letters may change in typified high-level taxa and the main concept behind the old name is easily recognisable. The addition of a type taxon for comparison and teaching is also an enormous advantage, including the diminution of the necessary effort of memory to learn names that have nothing to do with the included taxa names. An example is to be found for Arthropoda in table 4, following the endings presented in table 3. As can be seen, most of the resulting names are older than those in use, adding to an increasing stability of nomenclature (‘the older the name, the more difficult to find one displacing it’).
  But, what happens with non-typified nominal taxa? Starobogatov (1991) commented: ‘The most simple and radical solution is to reject all descriptive names and change them to typified names. . . . However, . . . such a sudden reform is absolutely impossible since it arouses a resolute protectiveness in all zoologists who are accustomed to certain names . . .’. Zoologists were also accustomed to names like Gephyrea or Vermes, which are no more in use. Some other ‘scientific’ names, like
Reptilia, are used in a more vernacular sense. Of course, implementation of a system of typified high-level names cannot happen overnight.
  The new Code should protect the use of typified names by making its naming mandatory side-by-side with non-typified names in those papers where new taxa are described. Descriptions of non-typified names should be considered unavailable. On the other hand, publication of uninominal names in the genus-group with the same endings as the ‘upper uninominal group’ names should also be prohibited, to avoid (hemi)homonymy. The implementation of obligatory registration of all zoological names could play a major role in eliminating errors. Non-typified names would eventually disappear. There are only two ways of keeping them, and both are far from satisfactory:
  (1) To maintain them for the lowest taxon (in a phylogeny) lumping together all the included taxa in a rank, e.g. genus. As has been repeatedly pointed out, this would make Amphibia Linnaeus, 1758 identical with, and having priority over, Vertebrata Lamarck, 1801, since it originally included the genus Petromyzon Linnaeus, 1758 (Class Cephalaspidomorphi). Moreover the name Nantes Linnaeus, 1758 (forming a taxon under his Amphibia) would also be a synonym, containing the same genus. Following this rule would undoubtedly change the meaning of many names.
  (2) The other possibility is typification based on one of the included typified taxa of lower rank (either families or genera). Since this has not occurred before, if the new Code allows it, it would lead to a frenetic race for type taxon designation and innumerable applications to the Commission to resolve conflicting typifications.
  Neither of these solutions is desirable. Non-typified names must disappear in 21st century zoological nomenclature.
  In the case of the few typified names having available names with the same precedence, a ruling of the Commission (acting as First Reviser or under the Plenary Power) selecting the most appropriate name after consulting with interested zoologists would be desirable, e.g. in the case of Order Coleoptera Linnaeus, 1758 (the original meaning included also cockroaches, crickets and earwigs!) that could be named (following the present proposal): Scarabaeiformes, Carabiformes,Hydrophiliformes, Staphyliniformes, Bostrichiformes, Cucujiformes, Cleriformes, Tenebrioniformes, Chrysomeliformes or Curculioniformes. There is also the possibility of taking into consideration the date of precedence of the non-typified name being replaced in the competition for naming higher rank taxa: e.g. the name Termitiformes 1802 would have precedence over Perliformes 1802 for the replacement naming of Polyneoptera Martynov, 1925 (with the appropriate ending change) since the first name is replacing Isoptera Brullé, 1832, which has precedence over the name Plecoptera Burmeister, 1839, replaced by Perliformes.
  The application of the system here presented would allow quick finding of available names for every desired category with information on authors and dates for the families included.

Table 4. Nomenclature of a subphylum of Arthropoda and of Order Coleoptera, following the present proposal in table 3. This is just a ‘scherzo’ and some names may have available alternatives. I have selected those I consider less disruptive. Some fossil taxa have not been considered, although in a formal proposal they should be, unless ruled otherwise.

Proposals to the Commission
  I expect that the aforementioned opinions and proposals will need to be considered by the compilers of the next edition of the Code. Those of us having a commitment to nomenclature must face the fact that conservatism is good up to a certain point, but can be counter-productive if maintained irrespective of necessary developments.
  I therefore urge the Commission to begin in-depth discussion of the abovementioned proposals (and of those of my predecessors) to identify those best meeting the needs of zoologists in the 21st century and to draft them for incorporation in the Code.
  Unlike Starobogatov, I will not propose a set of rules to be taken into consideration. Although I think that my proposals are logical and Code-compliant (with the suggested amendments), I consider that my fellow members of the Commission and, indeed, all working zoologists still have to give their views.
  However, my views can be summarised as follow: The new Code must regulate those uninomina above the family-group, usually known as phylum-, class- and order-group names.
  Non-typified names must be discarded in high-level taxa nomenclature. No new non-typified name will be available after the new Code is in force.
  Typified high-level regulated names must be introduced gradually and in accordance with the Code. Non-typified names in publications must be accompanied by the corresponding typified names, and use of non-typified names alone should be prohibited by the Code. New taxa described only under non-typified names should not be made available.
  A logical set of standardized connectors and endings, such as those proposed here (table 3), should be incorporated in the new Code.
Instead of creating either three groups above the family-group (phylum-group, class-group and order-group) or a single group encompassing all of them, I propose the expansion of the family-group name to form an ‘upper uninominal group’.
  This group would be typified by the names in the immediately inferior group (the genus-group) as is the standard in the present Code. This way, the internal logic of the Principle of Typification is maintained.
Depending upon the decision of the Commission, names for this ‘upper uninominal group’ could be taken directly from the existing family-group names or, alternatively, extant typified names for upper categories could enter into competition by precedence. It would not be necessary to give authors for these names. With this action, unnecessary efforts will be avoided, since most of the names needed are already available.

Acknowledgements
  I wish to thank here my colleagues and friends who discussed some of these points with me, and in particular David Remsen, whose help in querying the Nomenclator Zoologicus database in some particular cases has been much appreciated and has contributed greatly to this paper, and Manuel Sánchez-Ruiz for a critical reading of a first draft.

References

Kluge, N. Yu. 1996. Miphy v sistematike nasekomykh i printsipy zoologicheskoj nomenklatury. Entomologicheskoe Obozrenie, 75(4): 939–944.
Kluge, N. Yu. 1999. Mitos en sistemática y principios de nomenclatura zoológica. Myths in systematics and principles of zoological nomenclature. Boletín de la Sociedad Entomológica Aragonesa, 26: 347–377.
Papavero, N., Llorente-Bousquets, J. & Minoro Abe, J. 2001. Proposal of a new system of nomenclature for phylogenetic systematics. Arquivos de Zoologia, São Paulo, 36(1): 1–145.
Parker, S.P. (Ed.). 1982. Synopsis and classification of living organisms, 2 vols. 1166, 1232 pp. MacGraw Hill, New York.
Rasnitsyn, A.P. 1992. Comment on the article Problems in the Nomenclature of Higher Taxonomic Categories by Ya. I. Starobogatov. Bulletin of Zoological Nomenclature, 49(1): 62.
Rohdendorf, B.B. 1977. O ratsionalizatsii nazvanij taksonov vysokogo ranga v Zoologii. Paleontologicheskij Zhurnal, 2: 14–22. [Translated in Paleontological Journal, (1977) 11(2): 149–155; reprinted in Bulletin of Zoological Nomenclature, (1982) 39: 200–207].
Sibley, C.G., Ahlquist, J.E. & Monroe, B.L. Jr. 1988. A classification of the living birds of the world based on DNA-DNA hybridization studies. The Auk, 105(3): 409–423.
Starobogatov, Ya. I. 1984. O problemakh nomenklatury vysshikh taksonomicheskikh kategoriy. Pp. 174–187 in: Tatarinov, L.P. & Shimanskiy, V.N. (Eds.). Spravochnik po sistematike iskopayemykh organizmov (taksony otryadnoy i vyshchikh grupp). Izdatel’svo Nauka, Moscow.
Starobogatov, Ya. I. 1991. Problems in the nomenclature of higher taxonomic categories. Bulletin of Zoological Nomenclature, 48(1): 6–18.

General Article

Proposals for the incorporation of nomina of higher-ranked taxa into the Code

Alain Dubois
Muséum national d’Histoire naturelle, Systématique & Evolution, USM 602 Taxonomie & Collections, Reptiles & Amphibiens, 25 rue Cuvier, 75005 Paris, France (e-mail: adubois@mnhn.fr)

  Note. In order to avoid semantic ambiguity, the following terms (Dubois, 2000, 2005a-c) are used here: (1) nomen (plural nomina) for ‘scientific name’ in the Code (to avoid possible confusions with authors’ names, vernacular names, etc.); (2) nominal-series for a set of nomina that interact concerning synonymy, homonymy, priority, etc.: thus, family-series is used here instead of ‘family group’ as used in the Code, etc., to avoid confusions such as between the formula ‘species group’ to designate either a taxon or a nomenclatural level.

Introduction
  The Code currently regulates only the nomina of taxa of the species-, genus- and family-series, i.e. from the rank subspecies to the rank superfamily. For a short period, i.e. between the 1953 Copenhagen Congress (Hemming, 1953) and the 1958 London Congress, Rules for the naming of orders and other higher ranked taxa were incorporated in the international ‘Règles’, with use of type genera for such nomina (Linsley & Usinger, 1959), but these Rules had been deleted when the first edition of the Code (ICZN, 1961) was published. Currently these nomina are not covered by the Code, which raises increasing problems as new phylogenetic analyses of zoological groups are produced: such works usually tend to increase the number of higher taxa and to modify the contents and definitions of these taxa. The absence of Rules for the naming of higher taxa currently results in ambiguity and confusion, and if this situation persists it may result in chaos, different authors applying either the same nomen to different taxa or different nomina to the same taxon. This prompted me to propose formal rules for the incorporation of the nomina of higher taxa into the Code. These proposals are widely different and much more detailed than previous proposals already published in BZN (Rasnitsyn, 1982; Brothers, 1983; Starobogatov, 1991). Given the space limitations of this paper, they cannot be presented and discussed here in detail, but details of the project are provided elsewhere (Dubois, 2005a-c).

Premises
  The proposed Rules are presented here in the context of a philosophy of zoological nomenclature that relies on a few simple premises, in agreement with those of the Code for nomina of lower-ranked taxa (Dubois, 2005b):
  1. Nomenclature is distinct from taxonomy: the role of the latter is to define or recognize classificatory units or taxa, whereas the role of the former is to provide nomina for these units. Accordingly, nomina are just labels allowing unambiguous, universal and automatic designation of taxa within the frame of any given taxonomy. They are not taxa, or definitions of taxa, or theories about taxa, their properties or their evolution. They have no meaning or value in isolation. Their function is to allow storage and retrieval of taxonomic information about organisms, not to replace this information.
  2. Establishment of the status of a nomen is a three-step or three-storey process (Dubois, 2005a-b):
(a) Availability of a nomen is provided by its publication under certain conditions (date, Latin or Latin-like term, presence of a description, definition or indication purported to differentiate the taxon designated by the nomen).
(b) Allocation of a nomen to any potential taxon is not made through any kind of definition (be it phylogenetic, phenetic or other), but through the use of a tool unique to biological nomenclature, the ‘name-bearing type’ or onomatophore (Simpson, 1940, 1961), which establishes an objective and permanent link between the real world of organisms and the world of language (Dubois & Ohler, 1997; Dubois, 2005b). Onomatophores provide a means of ‘labelling’ taxa by ostension (Keller et al., 2003), but do not define taxa. Any onomatophore is included in several (usually many) more or less inclusive taxa of various hierarchical ranks, so that the nomen potentially applies to all of these taxa: which ones will in the end have to bear this nomen will be determined by the next step.
(c) In the three nominal-series covered by the Code, combination of the Rule of Coordination and of the Rule of Priority allows the automatic establishment of the hierarchical relationships between nomina designating more or less inclusive taxa. Among several nomina of which the onomatophores are included in a given taxon, the first published is the valid one, and this applies to taxa at all ranks including these onomatophores, up to the most inclusive one: at each rank, a more inclusive taxon bears the same nomen as its nominotypical subordinate taxon, which is the first named of all its subordinate taxa; this nomen may be either modified at different ranks as in the family-series, or not as in the other two nominal-series. Therefore, validity of nomen among several synonyms applying potentially to the same taxon is normally determined by priority of publication. However, in a few special cases, in order to preserve well-known nomina, this can be overruled by taking
prevalent usage into account.
  3. Nomina are historical entities with a given nomenclatural status (regarding their publication date and their onomatophore) which cannot be changed later. Under the Code, because of this ‘founder effect’, a nomen cannot be redefined after its creation. The only changes that can be brought to the nomenclatural status of nomina are through first-reviser actions, but such actions are strictly regulated and can occur only in a few situations, whenever some ambiguity remained after the original creation of the nomen (no onomatophore designation, contemporaneous publication of two synonymous or homonymous nomina, etc.).
  4. Ranking of taxa in the nomenclatural hierarchy does not provide any
information on the ‘nature’ or properties of taxa, but merely has the function of providing an organizational model (Knox, 1998) for indexing taxonomic information. This means that ranks are largely arbitrary and that by no means should a family of beetles be construed as equivalent by any criterion to a family of birds. However, in both groups any subfamily is subordinate to a single family and both taxa occupy a unique and identifiable place in the system, thus allowing unambiguous
allocation of any given organism to a single taxon bearing a single nomen, at all levels of the hierarchy.
  5. Although very important for communication, nomenclature is at the service of taxonomy, not the reverse, and nomenclatural rules should be devised in such a way as to be able to work simply and automatically, in order for two specialists working on opposite sides of the planet to be able to reach independently the same conclusion as to the valid nomen that a given taxon should bear within the frame of a given taxonomy. This means that the reply to the question ‘do we want a Code or a committee?’ (Fosberg, 1964) should clearly be ‘a Code’. Rules for the allocation of nomina to taxa should therefore be universal, simple, and leave no ground for personal opinions, tastes or interpretations. This is in contrast with the situation currently illustrated by supporters of the PhyloCode, an alternative nomenclatural
system, who are engaged in endless discussions about the status of nomina (e.g., Laurin & Anderson, 2004). We are at the beginning of the ‘century of extinctions’ (Dubois, 2003), and taxonomists, if they act responsibly, have other things to do than to quibble on the status of nomina: they must collect, study and describe our planet’s remaining species before they become extinct.

Differences
The proposed new Rules have been devised in agreement with these five premises. They differ from all previously proposed systems for the nomenclature of higher taxa (references in Dubois, 2005c) in several important respects:
  1. In all previous systems, two or more nominal-series were recognized above the family-series. In the new system, following the original proposal of Dubois (1984), a single nominal-series is recognized for higher taxa: the class-series. This is because, as stated above under 4, ranks are largely arbitrary, and there would be no point in discussing whether a given taxon ‘is’ a class or an order: the important point for communication among biologists is not the name given to the rank of the taxon, but the hierarchical arrangement of taxa among which this taxon occupies a unique position.
  2. Two other proposals of previous authors were not retained, for reasons explained in detail in Dubois (2005c): (a) the use of standard endings for class-series taxa of a given rank; (b) the use of a Rule of Coordination between nomina of the class-series: this means that, unlike the situation for the three nominal-series covered by the Code, a given class-series nomen can apply to only one taxon at a given hierarchical rank, not to several coordinate taxa (including ‘nominotypical’ taxa).
  3. Concerning the onomatophores of class-series nomina, previous proposals were in favour of designating either a type-genus or a type-family for each nomen. The latter proposal was rejected already in Dubois (1984, 1987). The former proposal, first adopted by Dubois (1984), proved to be impractical because of the absence of a Rule of Coordination for higher nomina. In the class-series, as no nominotypical taxa exist, with a single type-genus it would be impossible to know which nomen applies to the most inclusive taxon and which ones to any of its subordinate taxa having the same onomatophore. A new solution was therefore devised in order to allocate unambiguously each class-series nomen to a single taxon within the frame of a given taxonomy.

Rationale
  The rules proposed rely on a detailed rationale that cannot be fully described here, but the most noteworthy elements of which are briefly presented below:
  1. Availability of nomina of the class-series relies on criteria similar to those concerning other nomina governed by the Code: formal publication after 1757 in a permanent medium; nomen first created as a Latin or Latin-like term, or subsequently latinised if created in another language; nomen published associated with a diagnosis or definition of the taxon it designates, relying on ‘characters purported to differentiate the taxon’. Objective criteria are also proposed to distinguish between class-series and family-series nomina, a distinction which is not always easy.
  2. Allocation of nomina to taxa relies on onomatophores of a new kind, combined with a new tool called onomatostasis. This complication is needed in order to allow unambiguous allocation of each nomen to a single taxon in the hierarchical succession of taxa despite the absence of a Rule of Coordination.
(a) For reasons already explained by Dubois (1984, 1987), the onomatophores of class-series nomina should be genus-series nomina (nomina of genera or subgenera), not specimens or nomina of other nominal-series.
(b) It is proposed that the onomatophore of any class-series nomen be composed of its conucleogenera, i.e. the indissoluble set of all genus-series nomina referred to the taxon in the original publication. This set is indissoluble, which means that it is impossible to restrict it by exclusion of any genus-series nomen (unlike e.g. the situation in the genus-series, where a type-species may be designated among several originally included species). Application of the nomen will therefore be possible only to taxa that include all these conucleogenera: the exclusion of even a single one of them prevents application of the nomen to the taxon. However, this is not enough to know exactly to which taxon the nomen will apply whenever several (and often many) hierarchically related higher taxa include the same conucleogenera.
(c) In order to go further, it is proposed to take into account the alienogenera of the new taxon, i.e. the genera originally excluded from the taxon for which the new nomen was created, and which provided an external limit for this taxon.
(d) As usual in nomenclature regulated by the Code, the current allocation of a nomen to a taxon is not given once and for all at the creation of the nomen, but depends on the taxonomy adopted. A class-series nomen potentially applies to any higher taxon that includes all its conucleogenera, but its more precise allocation requires knowledge of the current taxonomic allocation of its alienogenera. Three different situations are possible, for which the following treatments are proposed:
(d) (1) Whenever a new nomen was proposed for a class-series taxon defined only by its conucleogenera (i.e., without mention of alienogenera), this nomen applies now to the least inclusive taxon, in the taxonomy adopted, that includes all its conucleogenera.
(d) (2) In both other cases, the new nomen was proposed for a class-series taxon defined both by its conucleogenera and its alienogenera. Two situations remain possible:
(d) (2) (1) All original alienogenera are currently extragenera, i.e. genera now placed in taxa excluded from the least inclusive taxon including all the conucleogenera. In such a case, the nomen now applies to the most inclusive taxon including all its conucleogenera and excluding all its extragenera. The latter play a new, particular role in zoological nomenclature: that of onomatostasis, i.e. they provide an external limit for the extension of the taxon designated by the nomen. In this case, the combination of onomatophore and onomatostasis provides a stable reference for the allocation of the nomen to a taxon, but this is true only as long as the taxonomy does not change, because
if it does some alienogenera may well become intragenera, as explained below.
(d) (2) (2) The original alienogenera include one or several intragenera, i.e. genera that are currently classified within the taxon that includes all the conucleogenera. In such a case, there is no onomatostasis and the taxon to which the nomen applies, just like in situation (d) (1), is the least inclusive taxon including all its conucleogenera.
  The process described above is illustrated in Fig. 1. More details and examples are provided in Dubois (2005c). Implementation of these Rules in any concrete situation results in a completely unambiguous allocation of any given nomen to a single taxon in the taxonomic hierarchy, despite the absence of a Rule of Coordination.
  (3) Among several synonyms applying to the same taxon, validity of one of them is established through the following succession of Rules:
(a) As with other nomina, the basic rule suggested here for validity of these nomina is priority of publication, concerning both synonymy and homonymy. Hopefully, if the Rules here proposed or Rules derived from them are incorporated into the Code, after their implementation Priority will become progressively the only principle regulating validity of higher nomina. However, as higher nomina have until now not been regulated by formal Rules, the sudden request for strict respect of Priority for nomina of the past would have dramatic consequences in some cases, as it would require the replacement of well-known nomina by poorly known or unknown nomina. In order to avoid these problems, attention has been paid to the need to protect well-known nomina even when they do not have priority to designate the taxa. However,
in order to avoid arbitrary decisions in this respect, strict Rules are needed to recognize these well-known nomina.
(b) The rationale used in this respect relies on making a difference between nomina used only among systematists (i.e., working on taxonomy, phylogeny or faunistics) and nomina used outside this community of specialists (i.e., among other biologists or even in the ‘general literature’). A nomen that is known and used only, even largely, among specialists of systematics, cannot be considered ‘well-known’ and worthy of protection or conservation simply on that account. If priority requires that this nomen be changed, all these specialists are (or should be) able to understand the reasons for this change, should not be perturbed by it, and should accept it, as nomina are just labels allowing unambiguous communication but have no meaning or value in isolation. On the other hand, nomina that have been regularly used in non-systematic literature, and are likely to be known to many biologists and even laymen, should be maintained for this reason. A criterion to recognize the fact that a nomen is well-known and widely used is its presence in the titles of publications, as titles have to be explicit enough to be understood even by non-specialists. Furthermore they are easy to find in bibliographic databases without having to read all publications in detail. These ideas led me to define strictly several categories of usage for nomina. More details on this rather complex matter are provided in Dubois (2005b-c), and only the final conclusions of this reflection are given here.
(c) Whenever working on the class-series nomenclature of a given zoological group, all nomina should be referred to one of the following categories: (A) symphonym: nomen used as valid for a taxon by all authors and in all publications after 31.XII.1899; (B) aphonym: nomen considered as available but invalid by at least one author and in at least one publication after 31.XII.1899; (C) eneonym: nomen never mentioned as available by any author and in any publication after 31.XII.1899; (D) diaphonym: nomen used as valid by at least one author and in at least one publication after 31.XII.1899. The last category includes two major subcategories: (C1) eurydiaphonym: nomen that has been significantly used as valid for a taxon in non-systematic literature after 31.XII.1899; (C2) stenodiaphonym: nomen that has not been significantly used as valid in non-systematic literature after 31.XII.1899. The subcategory of eurydiaphonym consists of two further infracategories: (C1a) paneurydiaphonym: eurydiaphonym that is the only one to have been used as valid for a taxon in non-systematic literature after 31.XII.1899; (C1b) schizeurydiaphonym: eurydiaphonym that has been used as valid for a taxon in non-systematic literature after 31.XII.1899, but alternatively to another eurydiaphonym for the same taxon. For the purpose of this Rule, the term significantly is to be understood as follows: to be considered a diaphonym, a nomen should have been used for a taxon, either in its Latin form or as a vernacular nomen in any recent language (A) either in the titles of at least 25 non-purely systematic books, written by at least 25 independent-authors and published in at least 10 different countries after 31.XII.1899, or (B) in the titles of at least 100 non-purely systematic publications of any kind written by 100 independentauthors and published in at least 10 different countries after 31.XII.1899. In what precedes: (a) purely systematic publications are publications dealing only or mostly with taxonomy, phylogeny and/or faunistics; (b) non-purely systematic publications are publications a significant portion of which (i.e., at least half of their total volume) deals with non-systematic matters, such asvarious fields of biology, medicine, agronomy, etc., or even is addressed to nonscientific users, such as members of administrations, governments, customs, conservation organizations, etc.; (c) independent authors are defined as authors who never published together (as co-authors) on the zoological group concerned before the case is considered (Dubois, 1997).

Fig. 1. Diagrammatic illustration of different kinds of relations between taxa (genera G1-G8, families F1-F4, orders O1-O2, class C1) in a given taxonomy (Fig. 1a) and twelve nomina N1-N12, originally proposed for taxa of the class-series including some of the genera G1-G8. Two major situations exist: (A) In one of them (Fig. 1b-d), all the genera originally placed in the taxon (its conucleogenera, which act as onomatophores for the nomina) are still placed in this taxon, and all the genera originally excluded from this taxon (its alienogenera) are now excluded from the taxon. The latter are therefore its extragenera and act as onomatostasis for the nomen. The nomen is then applied to the most inclusive taxon (i.e. of highest rank in the current taxonomy) including all its conucleogenera and excluding all its extragenera. In Fig. 1b, all genera originally placed in the taxon designated by the nomen N1 are still placed in the taxon O1, and all those of N2 are still in O2: the nomina N1 and N2 designate respectively the taxa O1 and O2. The same applies in Fig. 1c and 1d, although in these cases the conucleogenera and the extragenera represent only part of the genera, and even of the families, included in each order. (B) In the second situation (Fig. 1e-g), there is an overlap between the taxa as currently recognized and the taxa of the original taxonomy for which the nomina had been created, some alienogenera of the original taxon being currently included in the taxon. The nomen is then allocated to the least inclusive taxon (i.e. of lowest rank, in the current taxonomy) including all its conucleogenera. In some cases (Fig. 1f-g) this can result in two nomina initially created for taxa considered sister-taxa having now to be considered synonyms, although they do not share a single conucleogenus: this is the case of N9 and N10 in Fig. 1f and of N11 and N12 in Fig. 1g, all these four nomina designating the class C1.

(d) These detailed categories of nomina can be grouped in two major groups regarding their need for conservation: sozonyms (symphonyms and paneurydiaphonyms) and distagmonyms (eurydiaphonyms, stenodiaphonyms and aphonyms). Sozonyms are nomina which, being well-known to non-specialists, should be protected in their usual sense, even if this sense is not the original one at the creation of the nomen. In the latter case, the sozonym should be conserved, but credited to the first author who used it in the usual sense, i.e. with an onomatophore in agreement with its current usage. The earlier nomen with a different onomatophore should then be rejected as an invalid senior homonym. In contrast, distagmonyms do not have to be so protected. It is not proposed, however, to use strict priority to validate them, but to have a more sensible rule, according to which, if several nomina are available for a taxon, schizeurydiaphonyms have precedence over stenodiaphonyms, the latter over aphonyms and the latter over eneonyms. Only among these categories will priority allow a choice among competing nomina.
(e) These rules of validation of nomina are devised in order to take into account the long period during which higher nomina were not subject to any rules, to respect real usage outside specialized literature, and to allow a smooth transition into the future, when the automatic Principle of Priority will hopefully play a growing role in order to avoid prolonged debate to settle the valid nomen of any higher taxon.
(f) A single example will be given here to illustrate the difference between sozonyms and distagmonyms: that of the vertebrate class-series nomina AMPHIBIA and LISSAMPHIBIA (for more details, see Dubois, 2004). The nomen AMPHIBIA Linnaeus, 1758 was introduced for a taxon much more comprehensive than the current amphibians of all zoologists, as it included, beside them, several groups of ‘reptiles’ and ‘fishes’: according to the Rules of allocation of nomina to taxa presented above, this nomen applies to the taxon currently known as VERTEBRATA Cuvier, 1800. However, the nomen AMPHIBIA being a sozonym should be conserved in its usual sense, first found in AMPHIBIA
De Blainville, 1816: the latter should be validated as a sozonym, and its
senior homonym AMPHIBIA Linnaeus, 1758 definitively invalidated. Among amphibians, the nomen LISSAMPHIBIA Haeckel, 1866 was created for a taxon including the anurans and urodeles, but excluding the gymnophiones, thus being a strict junior invalid synonym of BATRACHIA Brongniart, 1800. Although in recent years the nomen LISSAMPHIBIA has had a growing use to designate a taxon including the anurans, urodeles and gymnophiones, this use is incorrect and the valid nomen of the latter taxon, according to the proposed Rules, is NEOBATRACHI Sarasin & Sarasin, 1890. The nomen LISSAMPHIBIA is completely unknown to non-specialists and, in contrast with the nomen AMPHIBIA, unlikely to be used in the titles of books written for a vast audience: it should be abandoned.
(g) The Rules presented above provide only a general framework for the
establishment of the valid nomen of a higher taxon. A number of particular cases, situations and exceptions remain, for which specific solutions had to be proposed. This information is given in Dubois (2005c), which also contains a detailed discussion of the use of ranks in higher (and lower) nomenclature, with proposals of standardization of the designation and treatment of nomenclatural ranks over the whole of zoology, a question that is not addressed here. The complete proposal is summarised under a set of 24 formal Rules.

Discussion and conclusion
  The proposed rules are offered to the community of zoologists and taxonomists for consideration and discussion, prior to their possible incorporation into the Code. They are considered to be an efficient way of solving the problems posed by the growing need to have rational and universal rules for the nomenclature of higher taxa, agreeing in their basic philosophy with the current rules of the Code. Attention is drawn here to the following major aspects of these rules: (1) they respect the
independence between taxonomy and nomenclature and do not ‘infringe upon taxonomic freedom’: they are thus compatible with any philosophy of classification, including ‘phylogenetic taxonomy’; (2) they allow nomina to be used according to their original sense, just as with other nomina covered by the Code, thus avoiding endless discussions and redefinitions of nomina, a major weakness of recent alternative proposals to the Code; (3) they are largely automatic in use, allowing any two zoologists confronted with the same problem to find the same solution by simple rigour, not through personal taste or opinion and without having to petition Committees or to rely on the help of lobbies; (4) once such Rules have been implemented, after a period of transition, the allocation of nomina to higher taxa will become a routine practice that will not require the expense of time, money and energy. Given the current state of our planet, the latter should be concentrated on the real priority of the beginning of the ‘century of extinctions’, which is not to redefine nomina, but to accelerate the exploration, inventory and study of organisms, in order in some cases to be able to struggle for their conservation, but in many more cases to simply (but importantly) store information and specimens for the future generations
(Dubois, 2003). In the light of these comments, the heavy investment of hundreds of working hours by dozens of zoologists to discuss pros and cons of a new proposal for an alternative Code appears at best as a mistake and at worst as a criminal operation against the study of biodiversity (Dubois, 2005b).
  In order to limit as much as possible the duration of the ‘period of transition’ mentioned above, it is proposed to build up a Nomenclator zoologicus for class-series nomina, i.e. a database of all zoological higher nomina ever published since 1758 with information on their status (date, conucleogenera, alienogenera), and with a possibility to find this information online. Work is in progress for the implementation of this database with its associated software (Dubois & Gérard, in preparation). Colleagues worldwide who are interested in this project are welcome to contact us.

References

Brothers, D.J. 1983. Comments on Rasnitsyn’s proposal to regulate the names of taxa above the family group. Bulletin of Zoological Nomenclature, 40(2): 72–73.
Dubois, A. 1984. La nomenclature supragénérique des Amphibiens Anoures. Mémoires du Muséum national d’Histoire naturelle, (A) 131: 1–64.
Dubois, A. 1987. Again on the nomenclature of frogs. Alytes, 6(1–2): 27–55.
Dubois, A. 1997. Proposals concerning the conditions needed for a name being eligible for conservation. In: Dubois & Ohler (1997): 317–320.
Dubois, A. 2000. Synonymies and related lists in zoology: general proposals, with examples in herpetology. Dumerilia, 4(2): 33–98.
Dubois, A. 2003. The relationships between taxonomy and conservation biology in the century of extinctions. Comptes rendus Biologies, 326 (suppl. 1): S9-S21.
Dubois, A. 2004. The higher nomenclature of recent amphibians. Alytes, 22(1–2): 1–14.
Dubois, A. 2005a. Propositions pour l’incorporation des nomina de taxons de rang supérieur dans le Code international de nomenclature zoologique. Biosystema, 23: 73–96.
Dubois, A. 2005b. Proposed Rules for the incorporation of nomina of higher-ranked zoological taxa in the International Code of Zoological Nomenclature. 1. Some general questions, concepts and terms of biological nomenclature. Zoosystema, 27(2): 365–426.
Dubois, A. 2005c. Proposed Rules for the incorporation of nomina of higher-ranked zoological taxa in the International Code of Zoological Nomenclature. 2. The proposed Rules and their rationale. Zoosystema, in press.
Dubois, A. & Ohler, A. 1997. Early scientific names of Amphibia Anura. I. Introduction. Bulletin du Muséum national d’Histoire naturelle, (4) 18(3–4): 297–320.
Fosberg, F.R. 1964. Do we want a Code or a Committee? Taxon, 13: 177–178.
Hemming, F. (Ed.). 1953. Copenhagen decisions on zoological nomenclature. Additions to, and modifications of, the Règles internationales de la nomenclature zoologique; approved and adopted by the Fourteenth International Congress of Zoology, Copenhagen, August, 1953. London, International Trust for Zoological Nomenclature: xxxi, 135 pp.
ICZN 1961. International Code of Zoological Nomenclature. First edition. London, International Trust for Zoological Nomenclature: xviii, 176 pp.
Keller, R.A., Boyd, R.N. & Wheeler, Q.D. 2003. The illogical basis of phylogenetic nomenclature. The Botanical Review, 69(1): 93–110.
Knox, E. 1998. The use of hierarchies as organizational models in systematics. Biological Journal of the Linnean Society, 63: 1–49.
Laurin, M. & Anderson, J.S. 2004. Meaning of the name Tetrapoda in the scientific literature: an exchange. Systematic Biology, 53(1): 68–80.
Linsley, E.G. & Usinger, R.L. 1959. Linnaeus and the development of the International Code of Zoological Nomenclature. Systematic Zoology, 8(1): 39–47.
Rasnitsyn, A. 1982. Proposal to regulate the names of taxa above the family group. Bulletin of Zoological Nomenclature, 39(3): 200–207.
Simpson, G.G. 1940. Types in modern taxonomy. American Journal of Science, 238: 413–431.
Simpson, G.G. 1961. Principles of animal taxonomy. New York, Columbia Univ. Press: xii, 247 pp.
Starobogatov, Y. I. 1991. Problems in the nomenclature of higher taxonomic categories. Bulletin of Zoological Nomenclature, 48(1): 6–18.

 

General Article

ZooBank: the open-access register for zoological taxonomy:
Technical Discussion Paper

Andrew Polaszek1,2, Miguel Alonso-Zarazaga3,1, Philippe Bouchet4,1, Denis J. Brothers5,1, Neal Evenhuis6, Frank-Thorsten Krell2, Christopher H.C. Lyal2, Alessandro Minelli7,1; Richard L. Pyle6, Nigel J. Robinson8, F. Christian Thompson9 & J. van Tol10

1International Commission on Zoological Nomenclature, London UK; 2Natural History Museum, London UK; 3Museo Nacional de Ciencias Naturales, Madrid, SPAIN; 4Muséum National d'Histoire Naturelle, Paris, FRANCE; 5University of KwaZulu-Natal, Pietermaritzburg, SOUTH AFRICA; 6Bishop Museum, Honolulu, Hawaii, USA; 7University of Padua, ITALY; 8Thomson Zoological Ltd, York, UK; 9Smithsonian Institution, Washington, DC, USA; 10National Museum of Natural History, Leiden, The Netherlands.

Introduction
  A proposal for the International Commission on Zoological Nomenclature (ICZN) to establish ZooBank, an open-access, mandatory registration system for descriptions of all new taxa and nomenclatural acts in animal taxonomy was published recently (Polaszek et al., 2005). That paper is effectively an argument for the establishment of a registration system, proposed by 29 currently active zoologists from a variety of backgrounds. The purpose of the present paper is to describe the technical details and possible obstacles to implementing such a system, and to attract comments and discussion from potential contributors and users.

ZooBank - Summary
  The widely dispersed nature of taxonomic publications that affect the scientific names of animals is an obstacle to progress in zoology. For example, in entomology alone, there are more than 1100 specialised journals that might contain taxonomically relevant information, and many of these are extremely difficult to access. With advances in bioinformatics answering the need for the more rapid description and cataloguing of our disappearing biodiversity, the necessity for an authoritative name registry is ever greater. Zoological Record has been the resource that until now has come closest to answering that need by its annual publication of all those new animal names and taxonomic acts in zoology that come to its attention. The producers of Zoological Record are therefore the ideal collaborators, with the Commission for the development and implementation of ZooBank. Zoological Record will act as the primary data collector with ICZN as the independent archiver of the database. The mechanism for doing this is described below.

The scope of ZooBank
  It must be emphasised that assessment or judgement of the taxonomic content of a piece of published work, i.e. any form of peer-review, is not part of the function of ZooBank. ZooBank will function as an archived index of zoological names and nomenclatural acts. A statement regarding the availability or unavailability of names will be provided. The full scope of nomenclatural acts indexed by ZooBank remains to be established, but should minimally include newly proposed names, and new nomenclatural acts that affect existing names as established in the Code.

Registration of Existing Names
  Retrospective registration of all existing names is clearly a major attraction of ZooBank, and one for which the collaboration with Zoological Record will prove indispensable. Zoological Record staff, during routine scanning and databasing of published articles, will supply ZooBank with all the data needed for registration, enabling the ICZN Secretariat to alert authors that their data are being registered. Similarly, Zoological Record will be alerted to any overlooked animal names and taxonomic acts via ZooBank. Free access to Zoological Record's Index of Organism Names (ION) will enable ZooBank to eventually become a complete database of all animal species. Such a complete list will serve many valuable functions that contribute to increased stability of zoological nomenclature.

Mandatory Registration
  In order for ZooBank to be a complete register of animal names and the nomenclatural acts that affect them, registration must be a mandatory requirement for availability according to the Code. A voluntary system, while potentially of some use, would negate the final aim of complete coverage. In the long term, mandatory registration should eventually apply to all zoological names and nomenclatural acts. A more practical approach for the short term, however, would be to require registration for all newly proposed names and nomenclatural acts, while accommodating voluntary registration of previously existing names and acts. Mandatory registration has the added advantage of ensuring that all new names and taxonomic acts are checked for compliance with the Code before they are made available.

Registration as Publication
  Several recent initiatives, particularly the NSF-funded Planetary Biodiversity Inventories (PBIs), are attempting to promote taxonomy as a largely web-based discipline (e.g., http://www.nhm.ac.uk/researchcuration/projects /solanum/). It seems inevitable that in the near future the Code will have to cover solely web-published taxonomic descriptions and nomenclatural acts. One possible response would be the development of a system whereby successful registration on the ZooBank database would be equivalent to publication. However, the implications of equating the act of registration in ZooBank as equivalent to publication via more traditional means (as prescribed in the current edition of the ICZN Code) are substantial, and demand careful consideration by a broad spectrum of the zoological research community.
  Paramount among the implications of a "registration=publication" scenario is the issue of peer review. While current provisions for peer review of taxonomic papers are often far from ideal, standards in taxonomy continue to be maintained largely by consensus. The fact that a carefully enforced peer review system would be an essential component of any "registration=publication" initiative provides an opportunity to reform current procedures. International editorial boards appointed for peer review of solely web-based taxonomic publications would need to be appointed to deal with web taxonomic publications in a systematic way. Collaboration with taxon-focussed learned societies could be a first step to the development of such review boards (e.g. International Society of Hymenopterists for Hymenoptera papers; etc), perhaps via the International Union of Biological Sciences (IUBS).

Changing the ICZN Code
  Mandatory registration as an additional criterion of availability under the ICZN Code will require substantial changes to several Code Articles. Changes to the Code can be implemented in one of two ways: as amendments to the existing (4th) edition, or in the context of a new (5th) edition. Introducing registration as a mandatory requirement for all newly established names and nomenclatural acts, while maintaining the current requirement for publication of such names and acts, could be established through amendments to the existing edition of the Code. More sweeping changes, such as equating the act of registration (with peer review) to publication, would probably best be introduced with a new (5th) edition of the Code.
  Article 16 of the ICZN constitution provides a clear protocol for introducing amendments that are major changes to the Code. In summary, the proposed amendments (as detailed below) need to be published (e.g. in Bulletin of Zoological Nomenclature, and possibly elsewhere) and comments from zoologists received within one year of publication. The International Union of Biological Sciences must be informed, and asked to approve the major changes. The Commission votes on the proposed amendments, and if approved by a two-thirds majority, requests IUBS to ratify the amendments. Alternatively, provisional ratification by IUBS can be requested at the same time as requesting approval (i.e. in advance of voting), in which case ratification becomes effective after the Commission's positive vote. After ratification, the Commission will publish the decision and date on which the ratified amendments come in to force. The entire procedure takes a minimum of 15 months.
  The process of drafting the 5th Edition Code has already started, with several aspects of the current edition in need of clarification or alteration. As with previous editions, extensive discussion with the Code's users is essential, but the completion of a 5th edition is targeted for 2008.
  Herein we describe two alternative approaches to revising the ICZN Code. The first approach assumes that new names and nomenclatural acts must be published according to rules that are already established in the current edition of the Code, and adds provisions for mandatory registration of new names and nomenclatural acts. These proposed changes are presented in the form of amendments to the existing (4th Edition) of the Code. The other approach represents changes that would not only require mandatory registration of new names and nomenclatural acts, but simultaneously establish a procedure where the act of registration itself constitutes an accepted form of publication alongside traditional publication of new names and nomenclatural acts. This second approach is presented in the form of changes to the ICZN Code as they would be implemented in a new 5th Edition of the Code. It would be premature in the context of this article to propose changes to the Code that would establish mandatory registration of all existing names; however, mandatory registration of certain existing names would be necessary in some cases, as described below.

Amendments to the current Code to accommodate mandatory registration
  The following amendments to the existing (4th Edition) Code would be necessary to minimally establish mandatory registration of new names and nomenclatural acts.

Add Article 16a. Mandatory registration of names published after 2007.
  16a.1. All new names and nomenclatural acts published after 2007 must be registered with the Commission within a period of two years from the date of publication to become available (in the case of names) or effective (in the case of nomenclatural acts).
  16a.2. If Art. 16a.1. is met, the date of publication is determined according to Art. 21, i.e. the date to be adopted is the date of publication and not the date of registration.
  16a.3. If a name is registered more than two years after its publication, the date of publication is the date of registration as determined by ICZN. An author who has missed the two-year registration period can apply to the Commission for backdating the names published to the original date of publication. Lost mail, force majeure, death of author, failings of publishers and similar hardships will be considered for accepting the original date of publication by the Commission.
  16a.4. Within a period of two years from the date of publication, a name cannot be declared to be unavailable solely because it is not registered. It has to be assumed that it is available.

Add Recommendation 16aA. Registration by authors. Registration is an integral component of the process of publishing new names. Authors must register new names immediately after publication or ensure registration by another person if they are not able to do it themselves.

Add Recommendation 16aB. Posthumous registration. If an author dies before registration, or in the case of posthumous publications, editors are requested to register new names with the Commission immediately after publication.

Add Recommendation 16aC. Late registration by the Commission. If a name has not been registered two years after its publication, the Commission must be informed. The Commission Secretariat will then register the name.

Amendment to Article 21.1.: Replace 'Except as provided in Article 3' by: Except as provided in Articles 3 and 16a.3'. Add: For names published after 2007 the date to be adopted is stated in the database of registered names.

Add Article 32.2.3. The spelling of names published after 2007 that are registered with the Commission can only be changed by use of the Commission's plenary power.

Add Article 52.8. Homonymy of registered names. Names registered after 2007 have no precedence over still unregistered older homonyms (regardless of whether the older homonym was published before 2008 or after 2007). If a registered name is a junior homonym, the Commission must be informed immediately.

Add Article 78.4.6. register all new names published after 2007, provide an open access database of these names and their original descriptions through the World Wide Web and maintain a paper archive of all original descriptions.

Add Article 80.10. Database of registered names published after 2007. New names published after 2007 must be registered by the Commission with the ZooBank database to be available for nomenclatural purposes. The status of registered names does not differ from the status of names published before 2007. They have no precedence over names published before 2007. The Commission will provide an open-access database, ZooBank, of registered names via the World Wide Web. If the open access or maintenance of this database cannot be provided for longer than 12 months, Article 16a will become inoperative until it is reinstated by plenary power.

Amendment to Article 83. Replace 'The Commission is under no obligation...' by: "Apart from the mandatory check for Code-compliance during registration, the Commission is under no obligation....."

The protocol that would be established through ZooBank for registering new names and nomenclatural acts under this procedure is described below.

1. Either prior to or after publication of a new name or nomenclatural act the author (or third party, see below) will log on to the ICZN website (www.iczn.org), or alternative approved site as listed on the ICZN website, and fill in the form provided. This form requests all details of the new name or nomenclatural act required for Code-compliance and to maintain completeness of ZooBank (a postal service will also be available for those without internet access).

2. A "nomenclatural act" includes the following: (i) the suppression of a name; (ii) the proposal of a replacement name; (iii) fixation of a spelling of a name; (iv) an emendation of a name; (v) fixation of a type species; (vi) first inclusion of nominal species in a genus-group taxon; (vii) designation of a lectotype; (viii) designation of a neotype; (ix) citation of the type genus of a family-group name published after 1999.

3. ZooBank will check the submitted details automatically, and the author will receive a response stating whether or not the name or act meets the provisions of the Code, and if a proposed name is a junior homonym. The author will be provided with a unique identifier (reference code: e.g. DOI/GUID/LSID) for each name or nomenclatural act. This identifier will be deposited in ZooBank but inaccessible to the general public until completion of the registration procedure. The identifier will be published in the subsequent paper.

4. After publication, and if available, the author will upload a facsimile file (currently pdf), or submit a reprint or good quality photocopy to the Commission Secretariat, for verification and archiving. Alternatively, the author can provide the registration details by post on a form downloadable from the ICZN website or available from the ICZN Secretariat. These electronic documents, although not mandatory, will become an integral part of ZooBank, and authors, editors and publishers will be strongly encouraged to supply them during the registration process. Copyright issues will need to be negotiated between publishers and ICZN.

5 . When the Commission Secretariat has received a copy of the original description or published nomenclatural act, this will be cross-checked with the registration form, checked for Code-compliance, and finally registered. In cases of non Code-compliance, the Commission will contact the author and withhold the registration process until a correction is published.

6. At the point of registration with ZooBank the submitting author will receive confirmation and details of the registration by e-mail or post. The name is now registered and available.

7. Copyright issues allowing, the complete original description will be linked to the registered name in the database immediately, and a paper copy archived in the archive of the Commission.

  The proposed registration procedure described above has a number of parallels with the current system for deposition of gene sequence data with GenBank (http://www.ncbi.nlm.nih.gov/Genbank/index.html).

Changes to the ICZN for Establishing Registration as Publication
  A somewhat more ambitious revision to the ICZN Code, which would both require registration for new names and nomenclatural acts, and simultaneously establish the act of registration as an alternative to, but running concurrently with, current publication requirements, could be implemented in the next (5th) Edition of the Code. Such a scenario would require at least the following changes to the current Code:

Change to Article 8.3. Replace “see Article 8.7.1” by: “see Article 8.8.1”.

Change to Article 8.5. Add “it” to the end of the sentence

Change to Article 8.5.1. Remove “it” from the beginning of the sentence

Add Article 8.5.2. is published on durable media, and

Change to Article 8.5.2. Replace “8.5.2” with “8.5.3”.

Change to Article 8.5.3. Replace “8.5.3” with “8.5.4”.

Change to Article 8.6. Addand before 2008” to the first sentence, after “produced after 1999”. ReplaceFor a work produced after 1999” in the second sentence with “For a work produced between 1999 and 2008”.

Add Article 8.7. Names and nomenclatural acts after 2007. All new names and nomenclatural acts proposed after 2007 must be properly registered with the official ICZN registry of zoological nomenclature [Article 17]. All such registrations entered after 2007 shall themselves constitute the equivalent of a “published work” as defined in this Chapter, and referenced elsewhere throughout this Code.

Change to Article 8.7. Replace “8.7” with “8.8”.

Change to Article 8.7.1. Replace “8.7.1” with “8.8.1”.

Change to Recommendation 8C. Replace “after 1999” with “between 1999 and 2008”.

Change to Article 9.8. Add before 2008” after parenthetical.

Change to Article 9.9. Replace full-stop (period mark) at end with “; or”

Add Article 9.10. after 2008 any form of information dissemination other than the official ICZN registry of zoological nomenclature [Art. 17].

Add Article 17. Mandatory registration of names and nomenclatural acts published after 2007.

17.1. Requirements for all names and nomenclatural acts. To be available, every new name and nomenclatural act proposed after 2007 must satisfy the provisions of Article 11 and Articles 13 through 16, and must al