Re: [Sansevierias] All change in Dracaena and Sansevieria

John,

Thanks for providing this information to the group.  Hermine and i have 
been aware of this dis-or con-junct reasoning for quite some time.  We 
joke about it often....

In my personal taxonomic opinion, IN MOST CASES, when a closely knit 
group provides a "distinct branch clade", that IS or SHOULD BE enough to 
create a separate genus!  IOW's, if a distinct clade branch does not 
provide essential differences for the creation of a distinct genus, then 
what does?

  As the brilliant cactological taxonomist Curt Backeberg stated long 
ago (1960) in his Cactus Lexicon, (remarking about the idiotic treatment 
of the genus Turbinicarpus by Lymon Benson) , he wrote: "In a 
sitituation like this, where each author is working along his own lines, 
in his own narrow specialism, the result is utter confusion.  The choice 
is clearly between the narrowly conceived genus, or a continuation 
without demarcations of the "lumping process", whereby the concept of a 
"type species of a genus" loses all meaning.  These attempted 
combinations start an unwarranted series of chain-reactions..........it 
should be stressed that in the case of the small genus, it is possible 
to have a clear mental image of a given group of characters, but an 
omnibus genus leads to a blurred picture of any diagnostic differences; 
and since not everyone who is dealing with a given plant-name is able to 
work through the increasing complicated literature, everything speaks in 
favor of the first of the alternatives stated above".

So, for me, Herm, and many others, the very idea of lumping Sansevieria 
with Dracaena is preposterous!!!  Regardless of their inward appearant 
genetics etc., Sans ALWAYS have fleshy, succulent leaves.  Dracaena's as 
we know them NEVER do.  All Sans can be propagated from leaf 
cuttings......Dracaena's cannot.  The flowering of a Sans abruptly ends 
the rhizome meristem (like an Agave etc.) while in Dracaena, flowering 
culminates in multiple continuous branch-growths...

So, if these characteristic differences don't clearly separate Dracaena 
from Sansevieria, then we might as well lump pines with Aracauria's 
(because both make woody cones), or cacti and roses, (because both make 
pretty flowers and have prickly things)

Obviously, i AM being sarcastic here, but i believe my point is 
thoroughly made

for the record....

mark
in the South of Florida







On 6/12/2014 2:59 PM, e-mail newearth [email protected] 
[Sansevierias] wrot
> All change in Dracaena and Sansevieria
>
> Dracaena and Sansevieria are very closely related. In the past as far 
> back as 1984 , studying West African species of Dracaena, observed 
> that the two genera are so closely related as to be congeneric. Recent 
> evidence from molecular studies supports this earlier hypothesis. Lu & 
> Morden (2014) included 34 species of Sansevieria in their study and 
> the resultant evolutionary (phylogenetic) tree shows these are nested 
> within Dracaena, forming a distinct branch(clade) within the tree. 
> Simply put Sansevieria are not distinct from Dracaena and must be 
> considered to be pat of an enlarged genus Dracaena
>
> This from a bigger article of the same name published in “Cactus 
> World” the journal of the British Cactus and Succulent Society Vol.32 
> #2 June 2014 pgs. 141-2.
>
>
> -- 
>
> /*See my photo Albums/sets here. 
> <http://www.flickr.com/photos/sansevieria02/sets/>*/
>
> /*"No One Lives Forever But We All Shine On"*/
>
> /*Cheers  John*/
>
> /*
> */
>
>