> You forgot D.neocaledonica.
Sorry, once again an inexcusable omission (even grouped *within*
Lasiocephala by Diels). But I think also this one entered the scene
after Lasiocephala sensu Planchon.
> Is there any Drosera pollen fossil from this period which
> matches any of the existing Subgen.Drosera? Or are they of a more
> primitive type?
The problem is how did an Australian _Drosera_ pollen of the primitive
type look like? Normally, rather straightforward tetrad grains are
assigned to Droseraceae, while it is in some cases even dubious if
such grains could belong to Nepenthaceae. So I fear little of more
detail can be actually deduced from fossil palynology at the moment.
I think there are some Tertiary finds from AU assigned to _Drosera_
but have to check the literature.
> I don't know if we can say that they styles in Lasiocephala are
> divided near the base in the same way as those of Subgen.Drosera. Looking
> at the drawings in Lowrie's latest article on petiolaris-complex taxa, the
> first division seems to occur halfway or 1/3 of the way up the styles,
> followed by numerous other divisions. I don't know about the other species
> in this group, but I believe it must be similar.
More or less. The basal, entire part of the style can vary in length,
however.
> To me this is rather dubious, with 2 possible interpretations.
> Maybe the common ancestor of Lasiocephala had 3 undivided styles,
I am rather convinced of that. At least at the base the styles were
entire. Otherwise, it would be difficult to imagine how Bryastrum
(always entire styles) should have developed. Reversals could be
an explanation, but I don't "like" them in theoretical reasoning.
> are as in
> Subgen.Meristocaulis, which began splitting at the apex. In time the
> divisions increased in number and moved down along the style. Or maybe
> the ancestor had basal bifurcations, as in Subgen.Drosera, which moved
> upwards along the styles and branched a few more times.
Have you considered Coelophylla (styles divided above centre) as a
possibility?
> (...) Maybe D.banksii is a recent step in the evolution of this
> group and not an old one.
>From the range it seems to be comparable in age to the _D.petiolaris_
complex.
RE: stigmata in _D.hamiltonii_
> >I would guess Diels but have to check it. At least I have reserved a
> >place in the primitive corner for Stelogyne. No problem to shift it
> >further "downwards". Thanks for highlighting this!
>
> Does anyone out there have a D.hamiltonii in flower at the
> moment or will have soon????? It apparently does have 3 carpels though, as
> do all other Drosera except Subgen.Thelocalyx. So the presence of 5
> styles, if confirmed, could still be a synapomorphic characteristic as
> that found in Lamprolepis.
I found no record of stigma numbers in my personal notes, so I seem
to never have doubted/checked the three presented by Diels, Marchant,
Takahashi, & Sohma. However, Allen Lowrie is not necessarily "wrong"
as I have observed deviations from the normal style numbers in some
other spp.. They are the rule rather than the exception in
Lamprolepis, and (rarely) occur outside this section as well. Lowrie's
photograph shows a trimerous ovary, so this seems to be a normal
flower (unfortunately the style is out of focus).
> >Interesting. This would be the first amphi-pacific species in
> >_Drosera_. Still the plants should be kept separate at some rank
> >because the disjunction is probably an old one.
>
> Just because Thelocalyx is an ancient group doesn't mean that the
> disjunction between both species itself is old.
Chorological reasoning indicates such, however. The W half of S AM
(especially Colombia and Ecuador) is excepted; rather unusual for a
recently formed area (which should be more continuous). The species
is/are widely distributed in both parts of the total (tropical) area,
not indicating a recent spread from a specific point of origin in one
partial area.
> OK, so you at least believe that Sect.Drosera is more or less
> homogeneous. So the big problem in your opinion is Sect.Oosperma and
> Ptycnostygma, right?
Oosperma, in the first line.
> I'm just being a perfectionist like you Jan!
It is nice to see that my "education" was not entirely fruitless :)
> >It is not the number but rather the geographic pattern. The
> >geographic distribution pattern of _D.peltata subsp.auriculata_
> >suggests allopatric speciation (in the E AU part of the range of
> >_D.peltata_).
>
> You can only really affirm this because D.peltata happens to have
> a very extensive range, but you can't say whether it and D.auriculata
> originated in W. or E.Australia.
If it originated in the W, some remnant should be found there.
> I think it is very important to remember that there is apparently a
> single D.peltata form in W.A.,
In W AU we have also _D.bicolor_ and _D.salina_. These could also
be considered subspp. (or rather vars. ?) of _D.peltata_ but at the
moment I see enough room for an argumentation to keep them separate
as spp. (especially as long as _D.insolita_ is a species, v.i.).
> N.Z., Japan, and elsewhere,
Although several forms were in fact described as infraspecific taxa
or even separate spp..
> while there are numerous D.peltata forms in SE Aust. There
> is actually someone at the moment in SE Aust. who believes that there are
> a few species present in this peltata-complex (which you would probably
> call subsp.) and is working on publishing them.
Really? Exciting! I hope this "someone" will consider the problem on
a world wide scale, not limited to SE AU.
> Maybe D.auriculata is truly a good species.
Barry Conn has discussed that in great detail, and I think he is
right.
> About that D.insolita, I imagine there are few colections of it,
I know of exactly one (1).
> but did any actually come with the tuber?
Yes, at least if I remember well.
> And if the differences are so few, why did you leave it as a
> separate species instead of putting it as a subsp. of D.peltata?
This would be a rather grave recombination based on a single
record. I simply did not dare to do it now. Further research will
show...
(NB: It may sound surprising but I even kept _D.burmannii_ and
_D.sessilifolia_ apart.)
Kind regards
Jan