The following is was cut directly from Rich Pyle's message on mailing list.

There is going to be an issue regarding how GUIDs (e.g., LSIDs) are assigned to taxon names to botanical vs. zoological names. This comes down to the fundamental difference in how zoologists and botanists think of a "name" (or as we informatics nerds would say, a "name object" -- the thing to which a GUID is attached and/or represents). Consider these hypothetical names:

Aus L. Xus Jones Aus bus Smith Xus bus (Smith)

The first clue to the differences between zoological and botanical practice is that the last of these would be represented as "_Xus bus_ (Smith) Jones", where Jones is credited as the first to have placed the species epithet "bus" within the genus "Xus".

In our (zoological) realm, we would certainly think of the "original genus" as an attribute of a species epithet (at the very least so that we know whether to put parentheses around the author), but otherwise we don't track combinations under ICZN (rules governing gender matching notwithstanding). To a zoologist, the combination is an attribute of the particular usage instance. For example, there may by five publications citing the species epithet "bus" and placing it in the genus "Aus" (one of these being the original description), and there may be five others placing "bus" within the genus "Xus". While it may very well be that Jones was the first to create this "Xus bus" combination, we in Zoology do not ascribe any special status to that event -- that is, we do not regard it as a Code-governed nomenclatural act.

Thus, from the Zoological perspective, there are three GUIDs (LSIDs) needed to accommodate the four items above:

LSID1: Aus L.
LSID2: Xus Jones
LSID3: bus Smith [original genus: LSID1]

We would then keep track of combinations through name-usage instances. For example, we might have ten records in out "usage instances" database to represent the five published citations of "Aus bus" and the five published citations of "Xus bus". These would all be thought of as usage intances of "bus" (LSID3), and an attribute each usage instance would be which genus combination it was placed with (five would point to LSID1 as the parent genus, and the other five would point to LSID2 as the parent genus). E.g.:

Usage#   NameID   ParentID
--------------------------------
  1      LSID3      LSID1
  2      LSID3      LSID1
  3      LSID3      LSID1
  4      LSID3      LSID1
  5      LSID3      LSID1
  6      LSID3      LSID2
  7      LSID3      LSID2
  8      LSID3      LSID2
  9      LSID3      LSID2
 10      LSID3      LSID2

From the botanical perspective, however, each combination is treated as a distinct (code-governed) "name" (Name-object). Thus, for botanists, there would be four GUIDs, instead of three:

LSID1: Aus L.
LSID2: Xus Jones
LSID3: Aus bus Smith
LSID4: Xus bus (Smith) Jones [basionym: LSID3]

For usage instance records, instead of having pointers to two GUIDs per record (one for the species epithet, one for the genus) there would simply be a pointer to the combination as used. E.g.:

Usage#   NameID
-------------------
  1      LSID3   
  2      LSID3   
  3      LSID3   
  4      LSID3   
  5      LSID3   
  6      LSID4   
  7      LSID4   
  8      LSID4   
  9      LSID4   
  10      LSID4   

I'll make two observations about this fundamental difference between the botanical and zoological approaches to "names" (name-objects):

1) It may be that this difference ends up being transparent, once we get this stuff implemented. In other words, there may be no problem with ZooBank? assigning GUIDs by the zoological tradition, and IPNI/IF assigning GUIDs by the botanical tradition -- as long as the informatics architecture, standards, and protocols are done right, there should be little difficulty aggregating botanical and zoological names data together. On the other hand, I can't help but think it will ultimately be to everyone's advantage to all be on the "same page" in terms of GUID issuance, so that there is no question how a GUID under one code corresponds to a GUID under another (in terms of what you do with the metadata attached to that GUID).

2) At first glance, the botanical approach might seem preferable because it leads to a (seemingly) simpler way of tracking the relationship between "names" and other data (like usages, specimens, etc.) However, I think there is compelling reason from an information management perspective (outside of personal biases of different taxonomic traditions) to treat "name objects" as monomial units (ala zoological tradition), and then layer everything else on top of usage instances (without the need to GUID-ify name-combination units in-between these two layers). But I'll save the details of this perspective for another discussion.

-- RogerHyam - 02 Mar 2007