Paleonet: two parts of holotype [SEC=UNCLASSIFIED]
Nikolaus Malchus
n.malchus at gmx.net
Tue Feb 12 14:14:38 GMT 2008
Dear colleagues,
here comes my resume. Thanks for your input!
MULTIPART HOLOTYPE DISCUSSION
The doubt concerns the application of holotype to a specimen consisting of more than one element (which is actually quite common): what does “ single specimen” (see 73.1) refer to in that case?
a) the entire organism including all it’s elements (when found together, and can be demonstrated to belong to the same individual) or does it mean
b) that a single element of a multi-element organism, should be chosen as the holotype that has fallen apart or has been disarticulated or dissected (for taxon ID)?
As far as I could learn from the discussion, the code’s definitions themselves allow for different interpretations. It may not be necessary, sometimes even contraproductive, to ask for a very narrow definition but it may be useful to ask for a clarification within the code in order to avoid discussions like the present one.
At present, it appears, that what counts is the first author’s choice, and to my personal taste, we can leave it there, but this should then be clearly stated, like:
A holotype may consist of a single element representing part of an organism or of all the elements of the same individual that have been found together by the first aurthor, (that have been shown by the first author to belong to one individual) and which have been designated by the first author as holotype(s).
Of course, Jere is right, the technical problem could be resolved by simply saying imperatively that the holotype in a multi-part individual must be a single element. But several scenarios come ad hoc to mind where this choice would create other problems:
- what about e.g. a dino skeleton: just the humerus (e.g., because it’s one piece) to be chosen although there are also the scull and vertebrae?
- to split hair here, what if the humerous is broken, ;-)?
- what about brachiopods, when you need x sections of them for determination: it will not be a single section but probably the 3D reconstruction that will determine the (new) species,
- as I understand Hottinger, not only the embryonic parts but the whole 3D reconstruction of macro-forams are important taxonomically, (though, I admit, this is not my specialty)
- or ostracodes (analogous to bivalves)
- or rudist bivalves: apart from two valves, very often you need to section them (longitudial, transversal, etc.,) to determine them or to demonstrate you have a new taxon. Some loose their ligamental crest during ontogeny, which part would you choose as the holotype then?
Cheers,
Niko
P.D. some extracts from the code:
72.5.
Eligibility as name-bearing types. Only the following are eligible to be a name-bearing type, or part of a name-bearing type, of a nominal species-group taxon:
72.5.1. an animal, or any part of an animal, or an example of the fossilized work of an animal, or of the work of an extant animal if the name based on it was established before 1931;
72.5.2. a colony of animals that exists in nature as a single entity, derived by asexual or vegetative multiplication from a single individual (e.g. a colony of cnidarians, such as corals), or part of such a colony;
72.5.3. in the case of fossils, a natural replacement, natural impression, natural mould, or natural cast of an animal or colony, or part of either;
72.5.4. in extant species of protistans, one or more preparations of directly related individuals representing differing stages in the life cycle (a hapantotype) [Art. 73.3];
72.5.5. a preparation for microscope examination (e.g. a "type slide") containing one or more individual organisms, in which the name-bearing types are clearly indicated and identifiable.
Recommendation 72C. Marking of important individuals. Whenever possible, authors establishing new nominal species-group taxa based upon microscope preparations containing more than one specimen (a "type slide") should mark distinctly the locations of specimens which are considered to be of crucial importance in demonstrating the taxonomic characters.
72.5.6. In the case of a nominal species-group taxon based on an illustration or description, or on a bibliographic reference to an illustration or description, the name-bearing type is the specimen or specimens illustrated or described (and not the illustration or description itself).
Article 73. Name-bearing types fixed in the original publication (holotypes and syntypes).
73.1. Holotypes. A holotype is the single specimen upon which a new nominal species-group taxon is based in the original publication (for specimens eligible to be holotypes in colonial animals and protistans, see Articles 72.5.2, 72.5.4 and 73.3).
73.1.1. If an author when establishing a new nominal species-group taxon states in the original publication that one specimen, and only one, is the holotype, or "the type", or uses some equivalent expression, that specimen is the holotype fixed by original designation.
73.1.2. If the nominal species-group taxon is based on a single specimen, either so stated or implied in the original publication, that specimen is the holotype fixed by monotypy (see Recommendation 73F). If the taxon was established before 2000 evidence derived from outside the work itself may be taken into account [Art. 72.4.1.1] to help identify the specimen.
73.1.3. The holotype of a new nominal species-group taxon can only be fixed in the original publication and by the original author (for consequences following a misuse of the term "holotype" see Article 74.6).
73.1.4. Designation of an illustration of a single specimen as a holotype is to be treated as designation of the specimen illustrated; the fact that the specimen no longer exists or cannot be traced does not of itself invalidate the designation.
73.1.5. If a subsequent author finds that a holotype which consists of a set of components (e.g. disarticulated body parts) is not derived from an individual animal, the extraneous components may, by appropriate citation, be excluded from the holotype (material may be excluded from a hapantotype if it is found to contain components representing more than one taxon [Art. 73.3.2]).
72.4.5. When an author designates a holotype [Art. 73.1], then the other specimens of the type series are paratypes. The latter do not become syntypes and cannot be used for lectotype selection [Art. 74] if the holotype is lost or destroyed; however, they are eligible for neotype selection (see Recommendation 75A).
type series, n.
The series of specimens, defined in Articles 72.4 and 73.2, on which the original author bases a new nominal species-group taxon. In the absence of a holotype designation, any such specimen is eligible for subsequent designation as the name-bearing type (lectotype); pending lectotype designation, all the specimens of the type series are syntypes and collectively they constitute the name-bearing type. Excluded from the type series are any specimens that the original author expressly excludes or refers to as distinct variants, or doubtfully includes in the taxon.
-------- Original-Nachricht --------
> Datum: Tue, 12 Feb 2008 09:41:15 +0100
> Von: Franz-Josef Lindemann <f.j.lindemann at nhm.uio.no>
> An: PaleoNet <paleonet at nhm.ac.uk>
> Betreff: Re: Paleonet: two parts of holotype [SEC=UNCLASSIFIED]
> For those who might find this discussion disproportionately pedantic I'd
> like to point out that the question has implications for, among other
> things, type collections. The number of holotypes in a collection might be
> considerably reduced if one had to downgrade counterpart specimens, only
> because they were not included in the original type designation.
>
> To be fair, it should be said that Jere did/does not exclude compound
> specimens as holotypes. In one of his contributions from last year he
> states: "Articulated individuals (for fossils with more than one element)
> are the best holotypes." I also think that his argumentation along the
> line
> of what the Code defines as a specimen and that the holotype is a specimen
> (article 73.1.), is sound. However, there is at least one other article
> that can be interpreted in a different (more biological) way. The
> incipient
> phrasing of Article 72.5 (on eligibility as name-bearing types) seems
> pertinent to me:
>
> Article 72.5 lists the sort of material (specimens) that is "eligible to
> be
> a name-bearing type, or part of a name-bearing type, of a nominal
> species-group taxon". I don't see how the specifier "or part of a
> name-bearing type" could be interpreted other than implying that the
> name-bearing type (e.g. the holotype) is the complete thing (individual).
>
> One might argue that the wording of the Code here is inconsistent with
> respect to how it elsewhere defines a specimen (and the holotype as a
> specimen), but what then is to be chosen as the correct understanding? At
> least from Article 72.5 one could conclude that those who formulated it
> had
> the individual in mind when referring to a name-bearing type at
> species-group level.
>
> fj
>
> At 07:43 12.02.2008, you wrote:
>
> >Jere,
> >
> >When you state that you stand by your previous opinions, does that
> include
> >the following?
> >
> >So, if I make 10 thin sections of a single individual, and only one of
> >them slices right through the proloculus, I can choose that section to be
> >the holotype and the others as paratypes or nothing at all, since they do
> >not show the distinguishing characteristics of my species concept. I
> >personally would make the critical thin section the holotype and the
> >others paratypes because I want my holotype to define as best as possible
> >and without any possible confusion my concept of my species. (yours
> >August-Sept 2007)
> >
> >Do you really think this is sensible? A single organism (there is no
> doubt
> >in your example) being both holotype and paratype or 'cited specimen' is
> a
> >ludicrous proposition. While I know much taxonomic emphasis is placed on
> >the arrangement of the proloculus in larger forams, it is conceivable
> that
> >in a future analysis it may turn out that the proloculus is only a minor
> >part of the story and something more important may lie away from your
> >'holotype' section (such changes in emphasis have happened in other
> >taxonomic groups). So your 'holotype' section may turn out to be less
> than
> >distinctive taxonomically. You may also neglect to inform your readers
> >that all your sections come from the same specimen (I certainly would!),
> >and some future palaeontologist may curse your name and decide that your
> >taxon is indecipherable, select a holotype for a new species from among
> >your 'cited' sections and relegate your species to the circular filing
> >cabinet (except for the purposes of homonymy). However, if you list all
> >the sections of your specimen as part of the holotype, and you get the
> >paper published, and subsequent palaeontologists do not suspect you as
> you
> >suspect Finlay, you are safe in the knowledge that apart from being
> placed
> >in synonymy, your species may be looked upon as a reasonable and useful
> >hypothesis.
> >
> >Above, you state that you want 'my holotype to define as best as possible
> >(sic) and without any possible confusion my concept of my species'. This
> >is exactly the reverse of what you may accomplish should you proceed with
> >your suggested method. Your individual organism, which you have sliced
> up,
> >has many characters which may not be present on your section cutting
> >through the proloculus. However, those characters do occur on the same
> >individual animal as the distinctive proloculus and are part of your
> >holotype (whether you like it or not). Should your 'paratypes' or 'cited
> >specimens' ever be separated (physically or conceptually) from your
> >holotype section, the understanding of your species is diminished. As I
> >think I said before, the fact you would even conceive of making an
> >individual organism both holotype and paratype or holotype and cited
> >specimen beggars belief.
> >
> >John
> >-----------------------------------------------------------------
> >Dr John R. Laurie
> >
> >Petroleum and Marine Division
> >
> >GEOSCIENCE AUSTRALIA
> >GPO Box 378
> >Canberra ACT 2601
> >Australia
> >
> >Tel: (02) 6249 9412; Fax: (02) 6249 9980
> >E-mail: John.Laurie at ga.gov.au
> >
> >Street Address:
> >Cnr Jerrabomberra Avenue & Hindmarsh Drive
> >Symonston ACT 2609
> >
> >ABN 80 091 799 039
> >----------------------------------------------------------------
> >
> >_______________________________________________
> >Paleonet mailing list
> >Paleonet at nhm.ac.uk
> >http://mailman.nhm.ac.uk/mailman/listinfo/paleonet
>
> Franz-Josef Lindemann
> Natural History Museum, University of Oslo
> P.O.Box 1172 Blindern, NO-0318 Oslo
> Phone: +47 22 85 16 59
> Fax: +47 22 85 18 00
> visiting address: Sars' gate 1, NO-0562 Oslo
>
>
> _______________________________________________
> Paleonet mailing list
> Paleonet at nhm.ac.uk
> http://mailman.nhm.ac.uk/mailman/listinfo/paleonet
--
**********
Nikolaus Malchus
Institut Català de Paleontologia, Fund. Privada
C/Escola Industrial, 23
08201 Sabadell
Catalonia, Spain
Tel +34 93 7266388
Fax +34 93 7276641
*****
abstracts, field guides and posters of the
International Congress on Bivalvia, Bellaterra, July 2006
http://www.senckenberg.de/odes/06-16.htm
**********
More information about the Paleonet
mailing list