>If we assume (I do so!) that
>the shift from pentamerous to trimerous ovaries has occurred but once
>in the genus, and if we consider the wide present distribution of
>Thelocalyx, it appears to be a good candidate for a starting point
>(i.e. in fact only a close derivative of the starting point) for the
>whole genus.
OK, in this I agree, that it would probably shift only once from
pentamerous to trimerous or vice-versa, and seeing that in Drosophyllum,
Dionaea, and Aldrovanda it is pentamerous, then I agree that Thelocalyx
could be the most primitive group.
>Lasiocephala shares distinctive features with subgen. Drosera (basally
>bifid styles, a very important synapomorphy in the latter!!),
>Bryastrum (subpeltate laminae, but styles **NEVER** divided to any
>degree), and Ergaleium (peltate laminae and divided styles but no
>stipules). It seems to be close to the origin of all these three very
>distinct subgenera and should therefore not be united with any of
>them.
The fact that bifid styles is synapomorphic in subgen.Drosera, to
me, suggests exactly that Subgen.Lasiocephala is derived from one of these
"more advanced" taxa from Subgen.Drosera.
>3.) Don't you think maybe subgen.Meristocaulis is closer to >
>subgen.Drosera than subgen.Lasiocephala? After all, D.meristocaulis >
>does have petiolate lamina
>
>So have many other subgenera.
Yes, obviously! This is just to say that the subpeltate lamina
seem to be synapomorphic and thus D.meristocaulis would share with
Subgen.Drosera the plesiomorphic non-peltated lamina and thus probably
closer.
>> and the single flowers on short scapes are found in
>> several species in subgen.Drosera, such as D.felix
>
>... which has ***divided*** styles.
Yes, that's my point. D.meristocaulis has 3 undivided styles. The
next natural step would be the 3 styles bipartite at the base found in the
"more primitive" taxa in subgen.Drosera, such as most of those found in
the New World. The next natural step would be the styles divided several
times at the apex as found in many subgen.Drosera taxa in S.Africa and in
Lasiocephala taxa.
The only problem is that in several other groups, including more
"advanced" ones, we find 3 styles which are only divided near the top,
and not at the base. But then there are also several in which there are
divisions halfway through or even all along the length of the style. Thus
the location of the divisions in the styles may be misleading and a
division originally near the base could have "moved" upwards and branched
a couple of times, resulting in something like that found in Lasiocephala.
This is just to say that 3 styles with no subdivision at the base may not
ALWAYS be plesiomorphic, especially when we look at the complex floral
morphology of the Aussie Drosera.
BTW, looking at Allen's CPs of Australia Vol.2, he shows that
D.hamiltonii has 5 styles fused at the base, yet Diels says that there are
only 3. Which is correct?
So anyways, single flowers on short scapes and 3 styles bipartite
at the base found in D.felix could be seen as a natural intermediate
between D.meristocaulis (with single flowers and 3 undivided styles) and
the taxa from Subgen.Drosera with 3 styles bipartite at the base and
several flowers per scape.
>> and D.uniflora.
>
>It has a short but distinct scape and *repeatedly divided* styles.
These are only divided at the tip, though, aren't they? In all
other species in your Sect.Ptycnostygma, the styles are divided at the
base and may be further divided near the apex.
>Yes, they are called "stalks", but they are *not* hairs but
>emergences.
What about the ones on the flower scapes? I believe these are
hairs and not emergences, correct?
>Yes but the pollen is different, and I think pollen morphology is
>important in infrageneric classification in _Drosera_.
Isn't polen of D.regia considered to be the most primitive
among Drosera? More than Thelocalyx? Yet if we consider that pentamerous
led to trimerous Drosera, than how could the more primitive polen be
explained in D.regia?
>> 7.) The difference in leaf length you point out between
>> D.sessilifolia and D.burmanni I believe is nonexistent. Apparently
>>the main differences are the leaf shape (which you mentioned), flower
>>color (pink and white, respectively)
>
>This is a weak character not reliably constant. I have tried to avoid
>it where possible in the key.
I agree flower color is weak, but you cut out my other comment on
the erect X ascending scapes. Also the leaves are more cuneate in
D.burmanni and more spathulate in D.sessilifolia.
Actually, I saw a few D.burmanni forms in Isao Takai's collection
here in Japan which left me a bit dubious as to whether D.sessilifolia is
a good species. These D.burmanni were all from Australia, from Allen
Lowrie's seeds. They were growing side-by-side in different pots, yet same
soil, and were so surprisingly different from each other! Some were truly
cuneate, but varied all the way to linear-spathulate!
> In fact, Oosperma is rather certainly inhomogeneous,
>and rearrangements will probably be necessary (like I have stated
>already in the article!). But I had to find a formal solution and had
>the least (NB: *not* none!) stomach ache with the version presented.
>Enough work for future researchers left.
Yes, but what I want to know is why you wanted to create a new
section (add more names to the confusion, as you often say) based on a
characteristic which is not so reliable and which you knew would separate
an inhomogeneous section into 2 inhomogeneous sections.
>> 10.) As to D.chrysolepis leaf shape, I'd say it's more lanceolate
>> than spathulate.
>
>The key says "oblong spathulate". The important point in the key is
>that it is decidedly "rounder" than "linear".
I think that's hard to say, it would be somewhere right in the
middle of both terms, if not more towards linear. The lamina is only
slightly wider than the petioles and is pointed at the apex. Maybe it
would be more correct as laceolate-spathulate.
>> 11.) As to D.villosa scapes, only those of the ex-D.ascendens
>> are glabrous (and even then only in the lowermost parts). Type
>> D.villosa have glandular + simple hairs thickly covering the scapes
>> and D.ascendens can be found with many variations of hair
>> distribution on the scapes.
>
>I would propose that you publish your stuff (or send me the
>*complete* manuscript with all systematic conclusions) on Brazilian
>species before we start discussing details. It seems that there will
>be severe rearrangements especially in this corner (you seem to want
>to reestablish all described microspecies and add some new ones). I
>can only use the data available to me. I can and will not comment on
>taxa like "ex-D.ascendens" & al.
The "ex" was not intended for you, since I know you know its
present taxonomic status. It was simply to make it easier to understand
for those who don't have Brazilian Drosera taxonomy at the tips of their
tongues and who represent 99.99% of the people in this listserv.
As to my publications, I'm working on them! And the main reason
why it's taking so long is because I want to include as much info as
possible to be sure I can convince people like you!
As to the info available to you, I was under the impression that
you had examined Saint Hilaire's type specimens, which includes
D.ascendens and D.villosa. I also had the impression that you at least had
read his original description of D.villosa where it does *NOT* say
glabrous scapes.
>> analysing herbarium specimens
>
>Which our friend from Australia has expressedly *NOT* done in this
>case.
Missing one characteristic doesn't mean he didn't see them.
>Yes. BTW "D.ericksoniae" is a synonym.
Of which? D.nitidula subsp.omissa (the true one)? I'm looking at
Allen's book now and though there are several similarities between his
D.ericksonae and D.nitidula, the styles of the former are really very
unique. If that is the true D.omissa Diels, than maybe that's how it
should remain, and not among the other taxa considered D.nitidula by
Allen in his book. BTW, according to his maps, these 4 taxa are all
sympatric with each other in at least a small area, with the possible
exception of his D.ericksonae and his D.nit.subsp.omissa.
>> 16.) Isn't auriculata sympatric with peltata, and thus shouldn't
>> it be a variety?
>
>It is perhaps partly, but AFAIK, _subsp.auriculata_ was never found in
>W AU. It is usually regarded to be the E AU part of the taxon. It
>should better not be a variety.
And since when do the 2 taxa have to be sympatric along their
whole ranges to be varieties and not subspecies? By what I know, if 2 taxa
occur together in at least one site, that's enough to put them as var. and
not subsp. If not, then in how many places do they have to occur together
to be considered truly sympatric? And to complicate the story, we have to
remember that sympatry is very relative, since often the plants may occur
in the same geographical region, but are widely separated ecologically and
never actually grow side-by-side.
As to your comment on D.insolita being synanthropous, I don't see
how that can be possible. In your key you say that it differs in having
crescentic leaves, etc., etc. You think it could've developed these
characteristics in maybe 100 or 200 years after being brought by British
colonists? Or when do you suppose it was introduced to Zaire by the
aborigenes?
Best Wishes,
Fernando Rivadavia
Tokyo, Japan