Hello Lycopus ..

When I learned the family ( In 1991 ) the new name was Fabaceae which in turn was divided into three subfamilies .. though the name Leguminosae was still retained and accepted as a valid synonym for Fabaceae. So Fabaceae did not replace Leguminosae.

Fabaceae ( Leguminosae )

Sub family :

Mimosoideae
Caesalpinoideae which contains Cercis
Papilionoideae

Thats the last time I looked. I am not aware that the sub families were seperated into seperate families. I can look up the other genera and let you know where they belong if you are interested. The flower structure is the key to seperating the sub families.

Good Day ...

I didn't realize that many of the new family names (Asteraceae, Brassicaceae, Poaceae, etc.) were synonyms. Every botanist that I knew insisted on using the new names, although I haven't asked anyone about them recently. Personally I like some of the old family names particularly Cruciferae and Umbelliferae.

Back to my original inquiry, I have looked over the ICBN rules and it would appear to answer my question in section 18.5

18.5. The following names, of long usage, are treated as validly published: Palmae (Arecaceae; type, Areca L.); Gramineae (Poaceae; type, Poa L.); Cruciferae (Brassicaceae; type, Brassica L.); Leguminosae (Fabaceae; type, Faba Mill. [= Vicia L.]); Guttiferae (Clusiaceae; type, Clusia L.); Umbelliferae (Apiaceae; type, Apium L.); Labiatae (Lamiaceae; type, Lamium L.); Compositae (Asteraceae; type, Aster L.). When the Papilionaceae (Fabaceae; type, Faba Mill.) are regarded as a family distinct from the remainder of the Leguminosae, the name Papilionaceae is conserved against Leguminosae.

It would appear valid to place Cercis, Gleditsia, and Gymnocladus in the family Caesalpiniaceae or to simply use the old Leguminosae or Fabaceae. I might just use Caesalpiniaceae because it is impressively long. :)

There is also this section. Although it is not really related it alludes to the wierdness that got me interested in this in the first place...

19.7. When the Papilionaceae are included in the family Leguminosae (nom. alt., Fabaceae; see Art.18.5) as a subfamily, the name Papilionoideae may be used as an alternative to Faboideae

Here is a link that might be useful: Leguminosae

The division of the Fabacea into three seperste families and the difference that you may see when a specific species depends on the theoertical out look of the author. You can divide botanist into two seperate categories lumper and spliters. Lumpers tend to take them simple and traditional view where all species with a reasonable amount of similiarities are 'lumped' into a single family. Spliters on the other hand take a far more specific look at phylogenies and like to subdivide families into more succinct and compact units.

If you look at the history of botanical biosystematics from Linneaus to the present your seein a refinement of technique and theory. Linneaus based his division first on sexual morphology and then worked his way out into other features which worked for the scientif methods he had available. As technology advanced such factors as cell cytology and dna analysis have shown that his system was flawed. As a result we are seeing new families being created, genera moving from one family to another etc. The people that tend to have the most problems with these moves are amatures and professional that are more in the agricultural end of plant sciences.

I didn't find any evidence that the separation was based on cytological or DNA evidence. It appears to be based on floral morphology. I've investigated most of the discrepencies that I have come across and have found most do not have anything to do with DNA evidence. The one exception I can think of is the restructuring of the genus Aster which was based on chromosome number. That still doesn't mean they lump all the plants with 2n=18 or whatever into the same group. They still maintain seperation based on morphological characteristics.

Another one that I came across yesterday was the placement of the genus Penthorum, specifically Penthorum sedoides. Most sources place it in the Crassulaceae, although from what I can gather all other members of that family have succulent leaves. One reference put it in Saxifragaceae. Still another one put it in it's own family, the Penthoraceae. Anyone want to take a crack at this one?

Linneaus system was artificial .. not based on evolution.

"As technology advanced such factors as cell cytology and dna analysis have shown that his system was flawed."

I would think Linneaus's system was changed long before DNA analysis ... studies of morphology are just as valid today as they ever were ... Linneaus system was one of the great artificial systems ...

"Anyone want to take a crack at this one? "

Not me !!!

Good Day ...

Before DNA Penthorum was usually placed in Saxifragaceae or sometimes by itself in its own family. DNA shows it closer to Crassulaceae, but even closer to Haloragaceae, so it could be treated as in a narrowly defined Penthoraceae, a broadly defined Haloragaceae or a probably too widely defined Crassulaceae.
DNA shows that Caesalpiniaceae is not monophyletic. Some Caesalpiniaceae are closer to Papilionaceae or to Mimosaceae than to other Cesalpiniaceae.

"I didn't realize that many of the new family names (Asteraceae, Brassicaceae, Poaceae, etc.) were synonyms. Every botanist that I knew insisted on using the new names, although I haven't asked anyone about them recently. Personally I like some of the old family names particularly Cruciferae and Umbelliferae."

Here's a list of the synonyms that I know of:

Old Name................New Name
Leguminosae..........Fabaceae
Compositae..............Asteraceae
Cruciferae..............Brassicaceae
Gramineae...............Poaceae
Labiatae................Lamiaceae
Umbelliferae............Apiaceae
Palmae..................Arecaceae
Guttiferae..............Clusiaceae

Are there any others?

I like some of the old ones better, too. In some cases, as with Compositae, they seem more desciptive.

While the traditional names Compositae, Cruciferae, Labiatae etc may have a certain appeal, the advantage of the alternatives with -aceae ending and genus name stem is that they are consistent in the way they are formed with all other plant family names. The name is instantly recognisable as being of family rank. And the system of nomenclature becomes simpler to teach.

I prefer to continue using some of the traditional names but in their English forms as common names, signifying any member of the family in question. Thus composite, crucifer, umbellifer, legume, labiate, palm.

As Nonmember pointed out, the 'Caesalpiniaceae' are an unnatural group based on DNA evidence. This finding strongly reinforces the case for recognising the legumes as a single family. It's possible that Faboideae and Mimosoideae will still be recognised as natural (monophyletic) subfamilies, but the Caesalpinioideae will presumably need to be divided into several subfamilies, and/or parts of it reassigned to the other 2 subfamilies.

Wow, some of you really sound like the top experts in the field. There is so much things here that I don't know at all or have little knowledge about, so thanks for sharing this information with us. Sharing is caring :)

With the array of sophisticated techniques available today and with the nomenclatural changes we have all experienced, it is futile for anyone but very competent taxonomist to attempt to classify plants. As to the assignment of family names, I would suggest using THE FLORA OF NORTH AMERICA as the final authority and cease bickering over family assignments.

This was a good discussion we had five years ago. Unfortunately the Flora of North America has not yet published the volume that include the Fabaceae. I am particularly looking forward to their treatment of Lamiaceae. The volumes that are complete are very good.

Remember however that even an authoritative source like FNA is not exempt from bias in making nomenclatural decisions. The individual chapters are written by specialists who, in many cases, have a stake in the nomenclature of the family, genus, etc. that is being discussed. So there will always be disagreements on these matters, and the "authority" of FNA or another standard stems from our willingness to accept it as the referree.