aaron floden
Mon, 04 Feb 2013 05:58:16 PST
 Hannon is correct, but not all taxonomists view classification schemes that way. The number of papers arguing species concepts are numerous and each argues for a certain way, or combination of ways to classify species: biogeographic, sexual, phenotypic, molecular, cytological, etc. 

It is not only different genera within different families that can differ in what species are.  Even within a genus subgeneric classifications can differ.  In Trillium you have the pedicillate species in the erectum-group which, according to DNA are a big complex of interbreeding populations without much delineation possible between them. On the other hand, you can grind up an uknown sessile species and have a very good idea (minus the western species) of what species it is. We had that problem last spring here in Tennessee where a landowner contacted us about a strange Trillium on their property. We went to collect a voucher, surveyed the area and some adjoining areas finding two additional sites, sequenced it because it seemed biogeographically impossible to be oostingii. DNA clearly showed it was distinct and sister to the lancifolium/recurvatum clade. Hopefully, as we continue to add samples the the clades get better resolution. Just need to add in
 the western sessiles aside from albidum.

 Another is Helianthus.... a mess where species get together and make taxomony nearly impossible for us to pigeonhole each "species" in our varying concepts or combination thereof.

 Molecular work is sorting out those anomalous genera and showing their phylogenetic relationships. Lycopus was recently placed into its on subtribe in the Lamiaceae. 

 Another problem in taxomony has been the eastern vs western North American concepts. The west has been viewed as topographically and geologically heterogeneous and therefore with more niches for endemics, thus far more localized species or taxa. In the east this has not been the case until fairly recently. Now that people have started to realize that there are distinct areas floristic areas these former areas are being reinvestigated. 


--- On Mon, 2/4/13, Rodger Whitlock <> wrote:

From: Rodger Whitlock <>
To: "Pacific Bulb Society" <>
Date: Monday, February 4, 2013, 9:03 AM

On 3 Feb 2013, at 12:55, Hannon wrote:

> a species of *Romulea* is not analogous to a species of *Aster* 

You deserve a prize for making a simple, but profound and important statement. 
It should be engraved in stone over the entrance to every herbarium.

I'm not kidding.

Rodger Whitlock
Victoria, British Columbia, Canada
Z. 7-8, cool Mediterranean climate

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