"Typotype" -- A Reply re Illustrations as lectotypes

[jr19]

William T. Stearn, in his masterful introduction to Linnaeus' Species
plantarum termed a specimen upon which an illustration was established as a
"typotype", an informal but exceedingly useful term.

For Linnaeus, many of his species were known to him only by a published
illustration. Over the centuries, it has been possible to closely examine the
holdings of many naturalists and it is often possible to find the specimen
used to prepare the illustration. The illustration, in such cases, is the only
"original material", and only it can be considered when selecting a lectotype.

In working with Plukenet names cited by Linnaeus, for example, it often
possible to find the specimen upon which the published figure was based.
Linnaeus never saw the specimen (he was denied access to the collection by
Sloane in the 1730s), so if a Plukenet illustration is selected as the type,
it and only it can be the lectotype. However, one can and should use the
actual specimen to understand the illustration; if the illustration is poor,
the specimen could be designated an "epitype". This is proving to be
especially useful for small or microscopic organisms (see Barrie et al. in
Taxon when we proposed the concept of using a designated specimen (epitype)
to interpret a poor or inadequate illustration).

You will find examples of ascertaining the identity of Plukenet illustrations
discussed in various papers of the Linnaean Plant Name Typification Project
authored by Charles Jarvis, Fred Barrie and/or myself.

In conclusion, the specimen upon which an illustration is based can not be
considered original material unless the author of the name actually examined
the specimen. The informal term "typotype" is available and used by many to
designate the specimen used to prepare an illustration. The Code address
this under the heading of "original material" in Art. 9.

Jim Reveal (MARY)