Taxonomy and its implication
for Data Management
Royal Museum for Central Africa
5 June 2013
Marc de Mayer
Taxonomy
 Science concerned with

Nomenclature: give ‘scientific’ names to species


Strictly regulated, different ‘codes’ for botany, zoology,
bacteria
Classification: create and name groups, ‘taxa’
 ‘Systematics’ is often used as an equivalent
(but actually the study of the kinds and
diversity of organisms)
Classification
 1,700,000 names! We need a system to
organise this information

Hierarchical classification
 Classification is based on phylogeny
(common descent)


Hypothesis: life only originated once; all
organisms descend from a single ancestor
Basis of objectivity in classification
Basic scientific name:
Genus species
 Any species should be named using the
binominal nomenclature:
Homo sapiens
Musca domestica
Basic scientific name:
Genus species
 Regulated by the codes:

Codes are drafted and maintained by Commissions




International Code for Zoological Nomenclature
International Code for Botanical Nomenclature
International Code for Bacterial Nomenclature
Commissions are arbiter in case of disputes
 Problem: many unicellular organisms are
neither plants nor animals, have two names
Availability of scientific name:






Published
Spelled in Latin letters (Latin or latinized word)
Written in italics
Genus with capital letter
Species without capital letter
Many additional rules
 Note: in botany we speak of ‘validity’ of name!
Publication
 Names have to be published to be available



Rules for availability are part of the code
Since 2012: web publication allowed!
Date of publication determines seniority of the
name

Important in case of dispute
 Start of the nomenclature:


Zoology: Linnaeus (1758). Systema naturae… 10th
ed.
Botany: Linnaeus (1753). Species plantarum. 1st ed.
Authority
 Author of the publication that contains the
description becomes ‘author’ of the taxon
name
 Date of description is the date that the
publication became publicly available

Not necessarily the same as the date on the cover
of the publication




Journals have a tendency to be published late
Reprint versus journal
Online publication versus printed publication
Differences in calendars (e.g. Russia in the beginning of
the 20th century; French revolution)
Authority
 Authority is very important in taxonomy,
often added to the name


For many journals mandatory for taxa of
rank genus and below
E.g. Homo sapiens Linnaeus, 1758


Zoology: with year of publication
E.g. Zostera noltii Hornemann

Botany: without year
Names are unique…
 … but not absolutely so


Botanical name can be same as zoological
There is no central register (yet), so this
leaves a lot of scope for mistakes

‘Preoccupied name’
 Has to be replaced with another name – ‘replacement
name’
 (have to check this: zoobank?)
Specific epitheton
 Second part of species name
 Is often an adjective

Takes gender from the genus name (which is always a noun)
 Can be other than adjective



Noun in apposition
Locality
Named after a person

genitive
Uni-, bi- et multinomens
 Names of rank of genus and above consist of a
single part

E.g. ‘Hominidae’, ‘Homo’
 Names of rank species and below consist of
several parts

E.g. ‘Homo sapiens’
 Subspecies… indicated with extra parts

E.g. ‘Homo sapiens erectus’
 Several name parts, one name
Classification can change
 Phylogeny = scientific study,


Research results can alter understanding
Interpretation of facts can be different between
scientists
 Difficult to construct a complete and consistent
classification
 Can result in name changes


Species moves from one genus to another…
Epitheton changes when genus has other gender
for those adjectives based on Latin or latinized
words
Higher classification: common
descent
Animalia
Arthropoda
Crinoidea
Holothuroidea
Echinodermata
Chordata
…
Asteroidea
Ophiuroidea
Echinoidea
Hierarchy: sub-sets
Biota
Animalia
Arthropoda Echinodermata
Crustacea
…
…
…
Plantae
…
Fungi
…
…
…
Hierarchy: ranks
Regnum: Animalia, Plantae…
Phylum: Arthropoda, Echinodermata…
Classis: Crustacea, Insecta…
Ordo: Decapoda, Amphipoda, Isopoda…
Familia: Xanthidae, Diogenidae…
Genus: Xantho, Progeryon…
Species: Xantho granulicarpus, Xantho
hydrophilus…
Extra ranks
 ‘Super-’, ‘Sub-’, ‘Infra-’


Subordo, infraordo, superfamilia…
Not for genus and species (except subspecies)
 Tribus: between family and genus
 Infraspecific


Subspecies only rank recognised in zoology
Botany: varietas, forma
 Botany: ‘Divisio’ instead of ‘Phylum’
Standard endings
Rank
Divisio
Subdivisio
Classis
Subclassis
Ordo
Subordo
Superfamilia
Familia
Subfamilia
Tribus
Subtribus
Botany
Bacteriology Zoology
(-phyta/-mycota)
(-phytina/-mycotina)
(-phyceae/-mycetes/-opsida)
(-phycidae/-mycetidae/-idae)
-ales
-ales
-ineae
-ineae
(-oidea)
-aceae
-aceae
-idae
-oideae
-oideae
-inae
-eae
-eae
(-ini)
-inae
-inae
Nomenclature
 Publication

To be valid, name has to be published in a
publication acceptable to the code
 Name has to be unique within the
domain of the code

Zoological name can be same as botanical
 Typification

Name has to be supported by a type
Name changes
 If a species is transferred from one genus to
another, the species’ name changes
 Zoology: the original author’s name is placed
between brackets


Spongia aurea Montagu, 1818
Hymeniacidon aurea (Montagu, 1818)
 Botany: parentheses + author of the new
‘combination’

Halophila stipulacea (Forsskål) Ascherson
Name changes
 Specific epitheton is often adjective, has to be
declined according to rules of latin grammar


Turbo littoreus Linnaeus, 1758
Littorina littorea (Linnaeus, 1758)
 But only if it concerns a Latin or latinized word!
 Specific epitheton can be noun, which has its
own gender


Tellina (Moerella) pygmaeus Lovén, 1846
Taxonomists, but especially other users of
taxonomic names, are often mistaken!

Tellina pygmaea: wrong!!
Validity of name
 Not the same as available.
 Zoology: oldest available name is the
valid name
 Note: in botany ‘valid’ is the same as
‘available’ in zoology. Here they speak of
‘accepted’
Validity of name
 Synomyms: two different names for the
same species. Oldest takes priority.
 (objective and subjective synonyms)
 Homonyms: one name for two different
species. Oldest takes priority.
 (primary and secondary homonyms)
Typification
 Type serves as an anchor, to stabilise
taxonomy
 Type of a species: specimen
 Zoology


Type of a genus: species
Type of a family: genus
 Botany: type is always a specimen
Typification
 Different kind of types:


Primary types and secondary types
Types fixed in original publication versus
later designation
Synonyms
 Objective synonyms

Preoccupied name…

Objective synonyms have the same type
 Subjective synonyms

An author has described a taxon, but a
subsequent author has stated that the
specimens of that species actually belong to
a taxon that has been described before
Interpretation of the literature
 Difference between misidentifications and
synonyms not always clear

List of names below a taxonomic name in a
taxonomic revision often contain both!
 Different authors use different classifications
 Importance of having an intelligent database,
that aids in interpreting names

Has to have information on synonyms, spelling
variations…
Problems with names
 With names themselves

Synonyms
 With identification


=applying name to specimen
Name will often depend on source of
information used

Need to document identification keys
 Problem integrating data from different
sources

Need for quality control
Types of tax info systems
 ‘Nomenclators’: list of names
 Taxonomic


List of names, plus taxonomic information (author,
reference for description publication…)
Who’s valid??
 Species database

Information on biology, identification…
 Distribution

For a group of species or for a region
Indexing literature
 Zoological record



Started 1864, now available electronically
Originally Linnaean Society, now commercial
Unfortunately ridiculously expensive
 Some free resources


http://www.organismnames.com
http://www.biologybrowser.com/
Nomenclators
 Index Kewensis

Included in the IPNI database,
http://www.ipni.org/index.html
 Index animalium

http://www.sil.si.edu/digitalcollections/indexanimalium/
 Nomenclator Zoologicus

http://www.ubio.org/NomenclatorZoologicus/
 Zoobank

http://zoobank.org/