[Taxacom] ICBN question

John McNeill johnm at rom.on.ca
Thu Jul 19 08:09:56 CDT 2007

Re the intended lectotypification paper described by Torbjörn Tyler <Torbjorn.Tyler at sysbot.lu.se> (Wednesday - July 18, 2007 7:21 AM) 

Karen Wilson <Karen.Wilson at rbgsyd.nsw.gov.au> (Wednesday - July 18, 2007 6:53 PM) wrote:
> This paper sounds like a good reason for proposing an amendment to the Code to allow for such cases, i.e. where a paper's subject is solely lectotypifications and that fact is stated in the introduction.

and Zack Murrell <murrellze at appstate.edu> (Wednesday - July 18, 2007 10:44 PM) wrote:
>I'm intrigued.  Where else would the lectotypification be, other than in the publication in which the typification statement appears?  What was the logic for "tightening" this rule?   Could you provide some examples of problems that had been encountered that necessitated this rule change?

As Dan Nicolson noted the ICBN’s requirement (Art. 7.11) is that a lecto-, neo-, or epi-typification is only effective (i.e. has priority) “on or after 1 January 2001, if the typification statement includes the phrase ‘designated here’ (hic designatus) or an equivalent.”

The majority of new typification statements appear in taxonomic revisions or monographs (the most appropriate place for them in my view) or even in Floras. There they are generally mixed with previously published typification statements.  The desirability of readily distinguishing new typifications is obvious.  Even when a publication is devoted entirely to typification, it is not uncommon for some previously published typifications to be included also, because of the benefit of bringing together often very scattered information.

But I believe that the prime reason for tightening up the requirement was to avoid unintentional and hence often ill-considered typifications.  Art. 9.8 of the ICBN provides that “the use of a term .. denoting a type, in a sense other than that in which it is so defined, is treated as an error to be corrected”, so when someone cites as “Type” what they believe to be the pre-existing type, perhaps even the holotype, when it is not, then they are held to have designated a lectotype if the element cited is part of the original material or a neotype if it is not.

A Special Committee on Lectotypification reporting to the International Botanical Congress in St Louis in 1999 recommended that from 2001 for any typification to be effective, it had specified that it was a new typification.  Hence the present rule of which Torbjörn Tyler‘s editor or typesetter seems to have been unaware.

My experience is that the benefits far outweigh any disadvantages, or which this is the first dramatic one of which I have heard.


John McNeill, Rapporteur-général, Nomenclature Section, IBC
    Director Emeritus, Royal Ontario Museum;
    Honorary Associate, Royal Botanic Garden, Edinburgh
Mailing address:  Royal Botanic Garden, Edinburgh, EH3 5LR, Scotland, U.K.
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e-mail: jmcneill at rbge.ac.uk (mail to johnm at rom.on.ca is also read)

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