1. The four basics of botanical nomenclature.

1.1. Application of names controlled by TYPES (Principle II).

1.2. Priority (Pr. III) of publication after STARTING POINT(s).

1.3. Priority applicable to competing names of same rank (Art. 11.2).

1.4. One correct name for a group with a particular circumscription, position and rank (Pr. IV).

2. The four possible statuses of botanical names.

2.1. Effectively/ineffectively published names (Art. 6.1 & 29-31) - minima for works in which names appear (not in lectures, etc.).

2.2. Validly/invalidly published names (Art. 6.2 & Arts. 32-45, etc.) - minimal information supporting effectively published names.

Art. 32 is general and references other Arts. Many complexities but 3 are basic: effectively published, correct form (Arts. 16-27, such as no tautonyms), and description/diagnosis or reference. Arts. 33-45 set further conditions (often after dates).

Note: Invalidly published names have no function in nomenclature.

2.3. Legitimate/illegitimate names (Arts. 6.3 & 6.4 refer to other Arts.). Concerns validly published names with specified 'fatal' flaws.

Two basic illegitimacies: superfluous renaming (Art. 52) [1 type, 2 names] and later homonym (Art. 53) [2 types, same name]. Note: Illegitimate names apply only in homonymy, have no other priority (see Art. 45.3) thus not basionyms (see Art. 49.1 and Art. 58.1).

2.4. Correct/incorrect names (Art. 6.5 refers to Art. 11) - concerns legitimate names pertaining to the same taxon [at the rank of family or below], one being correct, others incorrect (= synonyms).

Three parameters, controlled by taxonomy, affect correctness of a name and its synonymy: (1) circumscription (scope of the taxon), (2) position (in this genus rather than another), and (3) rank (a species, subspecies, etc.).

Effectiveness - has publication occurred?

Validity - does minimal required information accompany the effectively published name?

Legitimacy - not flawed as (1) 2 names for one type or (2) 1 (same) name for 2 types.

Correctness - the one 'right' name from all those applicable to the taxon.

3. Nomenclatural Types.

3.1. Definition: Constituent element(s) of a taxon to which the name is permanently attached (Art. 7.2) and controls the application of the name (Art. 7.1).

3.2. The seven basic kinds of Types.

3.2.1. Holotype: The one specimen or illustration used or designated by an author as the nomenclatural type (Art. 9.1).

3.2.2. Isotype: Any duplicate specimen (part of single gathering made by collector at one time) of the holotype (Art. 9.3, see footnote for definition of "duplicate").

3.2.3. Paratype: Specimen cited in protologue other than the holotype and isotype(s) (Art. 9.5).

3.2.4. Syntype: Any one of two or more specimens cited in the protologue when no [holo-]type was designated (Art. 9.4).

3.2.5. Lectotype: Specimen or illustration selected from original material when no type was indicated or is missing (Art. 9.2).

3.2.6. Neotype: Designated to serve as nomenclatural type if original material missing (Art. 9.6).

3.2.7. Epitype: Specimen or illustration selected to serve as interpretive type when type material cannot be critically identified for purposes of precise application of the name (Art. 9.7).

-onyms: acronym (Art. 60, Ex. 21), autonym (Art. 6.8, 7.6), basionym (Art. 33.3), homonym (Art. 48.1 (2 kinds, earlier and later), isonym (Art. 6, Note 1, Ex. 1 & 2), synonym (2 kinds, i.e taxonomic and nomenclatural), tautonym (Art. 23.4).

Warning: Names are different from what they apply to (taxa). A name has a type but no circumscription. Taxa have circumscriptions but no types. Thus, the name of a taxon is not the same as the taxon, just as your name is not the same as you. This is the key to discriminating between systematics (defining taxa), for which there is no Code, and nomenclature, for which there is a Code.

4. Standard botanical reference works.


4.1.1. Hawksworth & al. (1995) Ainsworth & Bisby's Dictionary of the Fungi. 9th ed., CAB International. - most recent edition. Much info but not on species.

4.1.2. Christensen. (1906) Index Filicum ... 1753-1905. Hafniae: H. Hagerup. 744 pp. With 6 supplements, the most recent being Johns, R. J. 1996. 1976-1990. Now in IK (see IPNI).

4.1.3 IK or Index Kewensis (2 vols. + 20 suppl., to 1995) - After Suppl. 16 (1971-1975) includes family, infrafamilial and infraspecific (but not infrageneric) names). Early vols. made taxonomic judgments (correct names in roman type and synonyms in italics). Those decisions, involving early taxonomic and nomenclatural opinions, are not necessarily correct by modern opinions. On CD-ROM (1996) and web as International Plant Names Index or IPNI

4.1.4. Gray Index or Gray Herbarium Card Index - generic, infrageneric, species and infraspecific names of flowering plants and pteridophytes of the New World published after 1893 (excludes names in first IK issue!). After 1987, issued in microfiche. After 1992 only on web. Now part of IPNI along with Australian Plant Name Index (APNI).

4.1.5. Pfeiffer, L. (1873-1874) Nomenclator Botanicus (4 vols.) - all plant names of classes, orders, tribes, families, divisions, genera, subgenera and sections before 1859. Vital for names above species rank. Entry to the early taxonomic history of any group. LITTLE KNOWN, time wasted as workers rediscover, if lucky and patient, what Pfeiffer gives.

4.1.6. Farr, E. & al. (1979) ING or Index Nominum Genericorum (Plantarum) (3 vols. & 1 Suppl. 1986) - Keystone of generic nomenclature, the only work accounting for the validly published generic names of ALL plants.

4.1.9. Reveal, J. L. (only on web) INSPVP or Index Nominum Supragenericorum Plantarum Vascularium Project. Index to suprageneric names of vascular plants.

4.1.7. Greuter, W. & al. (1993) NCU-3, Names in Current Use for Extant Plant Genera.. A mini-ING but including only generic names found to be in current use.

4.1.8. Brummitt, R. K. (1992) Vascular Plant Families and Genera. What Kew accepts.


4.2.1. Stafleu, F. A. & Cowan, TL-2 or Taxonomic Literature (2nd ed.) - Standard title & author abbreviations. Accounts for books by author (a few serials by editor) and gives dates of effective publication (not necessarily the title page date), vital in questions of priority.

4.2.2. Brummitt, R. K. & C. Powell, APN or Authors of Plant Names (1992). Good coverage of authors of scientific names.

4.2.3. Lawrence, G. H. M. & al., BPH or Botanico-Periodicum-Huntianum (1968). All botanical periodicals. Full titles cross-referenced with common and accepted abbreviations. Supplement (1991).

4.2.4. Royal Society of London, Catalogue of Scientific Papers (19 vols. covering, by author and date, papers published 1800-1900) - WIDELY UNKNOWN but to be checked if you know the author but not the journal abbreviation; gives title and pagination of each paper.

4.2.5. Index Herbariorum. I. The Herbaria, ed. 8. Holmgren, P. & al. 1990. Standard abbreviations of herbaria.

4.2.6 Index Herbariorum. II. Collectors. Lanjouw & al. 4 vols. 1954-1988. Who collected where & for which herbarium!


4.3.1. Index Londinensis (6 vols. & 1 Suppl. in 1941) - flowering plants and ferns illustrated before 1935 are listed by scientific name. Post 1935 in Isaacson's FPI or Flowering Plant Index (4 vols + 5, +3, last in 1997).


4.4.1. Blake, S. F. & Atwood, Geographical Guide to the Floras of the World - Part 1 (1942) floras of Africa, Australia, N. and S. America and islands of Atlantic, Pacific and Indian Oceans. Part 2 (1961) Western Europe.

4.4.2. Frodin, D. (2001, replaced 1984 ed.) Guide to Standard Floras of the World updates Blake & Atwood (adding omissions as Asia), excludes local floras.


4.5.1. Greuter, W. & al., (2000) ICBN or International Code of Botanical Nomenclature [St. Louis Code]. Regnum Veg. 138 - Articles (Rules) and Recomm. affecting nomenclature. Number of appendices, e.g.: naming hybrids and lists of conserved and/or rejected family, generic and species names.

4.5.2. Trehane, P. & al. (1995), ICNCP or International Code of Nomenclature for Cultivated Plants. Quarterjack Publishing. Only 40 pp. of Code.


4.6.1. Stearn, W. L. (1966 1st ed.) Botanical Latin . Latin is required for scientific names and, for valid publication of names, original diagnoses (after 1934 for all but fossils and algae, algae requiring it after 1957). For Latin help see

4.7. SUBJECT INDICES (is there a paper on a particular genus or subject?)

4.7.1. U.S. Dept. Agric. Library. BSI or Botany Subject Index. 15 vols. (1958). For 1903-1952. See Kew Record.

4.7.2. Kew Record of Taxonomic Literature, Vascular Plants (1971-date).

5. Some useful botanical works

5.1. Burdet, H. (1979) Auxilium ad botanicorum graphicem [Aid to the handwriting of botanists] from Geneva. - Based on collection started by A. P. de Candolle (1778-1841).

5.2. Mabberley, D. J. (1997 ed. 2) The Plant Book. Cambridge Univ. Press. 858 pp. - "Little David was small but Oh My!"

5.3. Stearn, W. L. (1992) Stearn's Dictionary of Plant Names for Gardeners. 363 pp. Cassell Publ. Ltd. - What a scientific name or epithet means; specifies generic gender!

5.4. Brown, Roland. (1956) Composition of Scientific Words. Fantastic tool! Currently for sale by the Smithsonian Press in paper-back. Also see Radcliffe-Smith.

5.5. Radcliffe-Smith, A. (1998) Three-language list of botanical names components.

5.6. Wiersema, J. & B. Léon. (1999) World Economic Plants. 747 pp. CRC Press. Excellent taxonomic website (English, Spanish or Portuguese!):

5.7. Jackson, B. D. (1928) A glossary of botanic terms. 4th ed. 481 pp., often reprinted. Great for terminology. But see Wagenitz, G. (1996) Wörterbuch der Botanik. 531 pp.

5.8. Nicolson, D. H. Proposal disposal. (Taxon 49: 549-554. 2000). 4500 proposals for conservation or rejection.

5.9. Davis, E. & D. Schmidt. (1996) Guide to Information Sources in the Botanical Sciences. 2nd ed. 275 pp. A little out-of-date but with excellent commentary.

5.10. Kunkel, G. (1990) Geography through botany. 334 pp. Recommended for baffling species epithets, like neoebudarum, sicula, that refer to now cryptic localities.

6. Some useful horticultural works

6.1. Armitage, A. M. (1997) Herbaceous perennial plants (ed. 2). 1141 pp. Identification, culture and garden attributes. Some illustrations.

6.2. Cope, E. A. (2001) Muenscher's keys to woody plants. 337 pp. Excellent for eastern US.

6.3. Dirr, M. A. (1998) Manual of woody landscape plants. 1187 pp. Identification, culture and garden attributes. Some illustrations.

6.4. Griffiths, M. (1994) Index of garden plants. 1234 pp. An updated Hortus III. Condensation of Huxley, A. (chief ed.). New RHS Dictionary of Gardening in 4 vols. Oriented toward British gardens.

6.5. Uva, R. H., Neal, & DiTomaso. (1997) Weeds of the Northeast. 396 pp. Excellent for weed identification, photographs of all stages (seeds, seedlings, plants in flower and in fruit).

Warning: The type of a generic name is not a species but the name of a species.

Dan H. Nicolson 07 June 2002