Abstract
The use of the term ‘diagnosis’ and of related terms (‘character’, ’description’, ‘definition’, etc.) in the two related fields of taxonomy and nomenclature is quite confusing. The purpose of this work is to propose an unambiguous terminology for these terms, and to discuss the use of diagnoses and related concepts in these two disciplines. In taxonomy, the different kinds of ‘diagnoses’ one uses provide different kinds of information about organisms, their characters and their relationships, and they should be used together rather than be mutually exclusive. In nomenclature, the current Rules of the Code that concern the use of ‘descriptions’ and ‘definitions’ are unclear. Articles 13.1.1 and 75.3.2 are ambiguous, as they allow both a ‘strict’ and a more ‘inclusive’ interpretation. Proposals are offered to improve them.
References
Anonymous [International Commission on Zoological Nomenclature] (1999) International code of zoological nomenclature. Fourth edition. London (International Trust for zoological Nomenclature): i–xxix + 1–306.
Ashlock, P. D. (1971) Monophyly and associated terms. Systematic Zoology, 20: 63–69. <https://doi.org/10.2307/2412223>.
Ashlock, P. D. (1985) A revision of the Bergidea group: a problem in classification and biogeography (Hemiptera-Heteroptera: Lygaeidae). Journal of the Kansas entomological Society, ‘1984’, 57 (4): 675–688.
Cantino, P. D. & de Queiroz, K. (ed.) (2010) International code of phylogenetic nomenclature. Version 4c. 1–102. <http://www.ohio.edu/phylocode/PhyloCode4c.pdf>.
Ceríaco, L. M. P., Gutiérrez, E. E., Dubois, A. et al. [490 additional signatories] (2016) Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa, 4196 (3): 435–445. <https://doi.org/10.11646/zootaxa.4196.3.9>.
De Queiroz, K. & Gauthier, J. (1990) Phylogeny as a central principle in taxonomy: phylogenetic definitions of taxon names. Systematic Zoology, 39: 307–322. <https://doi.org/10.2307/2992353>.
De Queiroz, K. & Gauthier, J. (1994) Toward a phylogenetic system of biological nomenclature. Trends in Ecology & Evolution, 9: 27–31. <https://doi.org/10.1016/0169-5347(94)90231-3>.
Dubois, A. (1981) Hybridation interspécifique et notion du genre en zoologie. Comptes rendus des Séances de l’Académie des Sciences, (3), 292 (A): 201–203.
Dubois, A. (1988) The genus in zoology: a contribution to the theory of evolutionary systematics. Mémoires du Muséum national d’Histoire naturelle, (A), 140: 1–123.
Dubois, A. (1997) An evolutionary biologist’s view on the science of biology. Alytes, 15 (3): 133–136.
Dubois, A. (1998) List of European species of amphibians and reptiles: will we soon be reaching “stability”? Amphibia-Reptilia, 19 (1): 1–28. <https://doi.org/10.1163/156853898X00304>.
Dubois, A. (1999) Miscellanea nomenclatorica batrachologica. 19. Notes on the nomenclature of Ranidae and related groups. Alytes, 17 (1–2): 81–100.
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. <https://doi.org/10.1016/s1631-0691(03)00022-2>.
Dubois, A. (2004) Developmental pathway, speciation and supraspecific taxonomy in amphibians. 2. Developmental pathway, hybridizability and generic taxonomy. Alytes, 22 (1–2): 38–52.
Dubois, A. (2005) 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. (2006a) Incorporation of nomina of higher-ranked taxa into the International Code of Zoological Nomenclature: some basic questions. Zootaxa, 1337: 1–37.
Dubois, A. (2006b) Naming taxa from cladograms: a cautionary tale. Molecular Phylogenetics & Evolution, 42: 317–330. <https://doi.org/10.1016/j.ympev.2006.06.007>.
Dubois, A. (2007a) Phylogeny, taxonomy and nomenclature: the problem of taxonomic categories and of nomenclatural ranks. Zootaxa, 1519: 27–68.
Dubois, A. (2007b) Naming taxa from cladograms: some confusions, misleading statements, and necessary clarifications. Cladistics, 23: 390–402. <https://doi.org/10.1111/j.1096-0031.2007.00151.x>.
Dubois, A. (2008) Phylogenetic hypotheses, taxa and nomina in zoology. In: A. Minelli, L. Bonato & G. Fusco (ed.), Updating the Linnaean heritage: names as tools for thinking about animals and plants, Zootaxa, 1950: 51–86.
Dubois, A. (2010) Retroactive changes should be introduced in the Code only with great care: problems related to the spellings of nomina. Zootaxa, 2426: 1–42.
Dubois, A. (2011a) The International Code of Zoological Nomenclature must be drastically improved before it is too late. Bionomina, 2, 1–104. <https://doi.org/10.11646/bionomina.2.1.1>.
Dubois, A. (2011b) Species and ‘strange species’ in zoology: do we need a ‘unified concept of species’? Comptes rendus Palevol, 10: 77–94. <https://doi.org/10.1016/j.crpv.2011.01.002>.
Dubois, A. (2017a) A few problems in the generic nomenclature of insects and amphibians, with recommendations for the publication of new generic nomina in zootaxonomy and comments on taxonomic and nomenclatural databases and websites. Zootaxa, 4237 (1): 1–16. <https://doi.org/10.11646/zootaxa.4237.1.1>.
Dubois, A. (2017b) The need of reference specimens in zoological taxonomy and nomenclature. Bionomina, 12: 4–38. <https://doi.org/10.11646/bionomina.12.1.2>.
Dubois, A. & Nemésio, A. (2007) Does nomenclatural availability of nomina of new species or subspecies require the deposition of vouchers in collections? Zootaxa, 1409: 1–22.
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.
Dubois, A., Ohler, A. & Biju, S. D. (2001) A new genus and species of Ranidae (Amphibia, Anura) from south-western India. Alytes, 19 (2–4): 53–79.
Dubois, A. & Raffaëlli, J. (2009) A new ergotaxonomy of the family Salamandridae Goldfuss, 1820 (Amphibia, Urodela). Alytes, 26 (1–4): 1–85.
Dubois, A. & Raffaëlli, J. (2012) A new ergotaxonomy of the order Urodela Duméril, 1805 (Amphibia, Batrachia). Alytes, 28 (3–4): 77–161.
Haeckel, E. (1866) Generelle Morphologie der Organismen. Zweiter Band. Allgemeine Entwickelungsgeschichte der Organismen. Berlin (Georg Kramer): i–clx + 1–462, pl. 1–8. <https://doi.org/10.1515/9783110848281>.
Hennig, W. (1950) Grundzüge einer Theorie der phylogenetischen Systematik. Berlin (Deutscher Zentralverlag): i–vii + 1–370.
Hennig, W. (1966) Phylogenetic systematics. Urbana, Chicago & London (University of Illinois Press): i–vii + 1–263.
Keller R. A., Boyd R. N. & Wheeler Q. D. (2003) The illogical basis of phylogenetic nomenclature. The botanical Review, 69: 93–110. <https://doi.org/10.1663/0006-8101(2003)069[0093:TIBOPN]2.0.CO;2>.
Laurin, M. (2005) The advantages of phylogenetic nomenclature over Linnean nomenclature. In: A. Minelli, G. Ortalli & G. Sanga (ed.), Animal names, Venezia (Instituto Veneto di Scienze, Lettere ed Arti): 67–97.
Lee, M. S. Y. (1998) Ancestors and taxonomy. Trends in Ecology & Evolution, 13: 26. <https://doi.org/10.1016/S0169-5347(97)01272-X>.
Mayden, R. L. (1997) A hierarchy of species concepts: the denouement in the saga of the species problem. In: M. F. Claridge, H. A. Dawah & M. R. Wilson (ed.), Species: the units of biodiversity, London (Chapman & Hall): 381–424.
Mayr, E. & Ashlock, P. D. (1991) Principles of systematic zoology. Second edition. New York (McGraw-Hill): i–xx + 1–475.
Meyer, A. (1926) Logik der Morphologie im Rahmen einer Logik der gesamten Biologie. Berlin (Julius Springer): i–vii + 1–290. <https://doi.org/10.1007/978-3-642-50733-5>.
Ohler, A. & Dubois, A. (2012) Validation of two familial nomina nuda of Amphibia Anura. Alytes, 28 (3–4): 162–167.
Otte, D. & Perez-Gelabert, D. (2009) Caribbean crickets. The Orthopterists Society: [i–iv] + 1–792.
Pearsall, J. (ed.) (2001) The new Oxford dictionary of English. Oxford (Oxford University Press): i–xxi + 1–2152.
Plateaux, L. (1981) Critère mixiologique et notion de genre. Bulletin de la Société zoologique de France, 106: 513–520.
Simpson, G. G. (1940) Types in modern taxonomy. American Journal of Science, 238: 413–431. <https://doi.org/10.2475/ajs.238.6.413>.
Simpson, G. G. (1945) The principles of classification and a classification of mammals. Bulletin of the American Museum of natural History, 85: i–xvi + 1–350.
Simpson, G. G. (1961) Principles of animal taxonomy. New York (Columbia University Press): i–xii + 1–247.
Sneath, P. H. A. (1962) The construction of taxonomic groups. In: Microbial classification, Symposia of the Society for general Microbiology, Cambridge, U.S.A. (Cambridge University Press), 12: 289–332.
Sokal, R. R. & Michener, C. D. (1958) A statistical method for evaluating systematic relationships. University of Kansas Science Bulletin, 38: 1409–1438.
Van Gelder, R. G. (1977) Mammalian hybrids and generic limits. American Museum Novitates, 2635: 1–25.
Van Regenmortel, M. H. V. (2016) Classes, taxa and categories in hierarchical virus classification: a review of current debates on definitions and names of virus species. Bionomina, 10: 1–21. <https://doi.org/10.11646/bionomina.10.1.1>.