Date: Mon, 28 Jun 1999 20:35:13 PDT From: Fernando Rivadavia Lopes <fe_rivadavia@hotmail.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg2691$foo@default> Subject: The Veredas Expedition: part 4
.....
So now let's move on to what was probably the main motivation of this trip:
the D.hirtella-complex. Here's everything you've ever wanted to know about
the D.hirtella-complex, but were always afraid to ask -- and will regret
having asked by the time you're finished reading this!! Anyways, it all
started when....
Saint-Hilaire described two varieties for this species: D.h. var.hirtella
and D.h. var.lutescens, both from the Serra dos Pirineus in Goias. Until
recently, I knew the latter only from the Chapada dos Guimaraes in S Mato
Grosso state while the former was very familiar to me from Minas Gerais
state, where it is common. I had also seen var.hirtella in N Goias state at
the Chapada dos Veadeiros where it was extremely common and variable, but
had not been able to find it at the Chapada Diamantina in S Bahia state
where one collection is known.
Then two years ago, while on leave from Japan and vacationing in Brazil
(driving all around studying CPs), I accidentaly discovered where in Goias
was the Serra dos Pirineus. Earlier that week, I had already discovered a
new taxon belonging to the D.hirtella-complex, first on a hill in the middle
of our capital, Bras\355lia, and then again at the Chap.dos Veadeiros. I'd
called it D.sp."white hirtella" because its most outstanding characteristic
were the white hairs on the scapes, instead of red like hirtella and yellow
like lutescens. Also, the scapes were erect while in the other two varieties
they are more or less ascending.
Anyways, on my last day at the Chap.dos Veadeiros before heading back to
S.Paulo, I accidentally discovered where the Serra dos Pirineus was while
talking to a local guide and friend. So I decided to stop there briefly and
take a quick look. And what a mind-boggling day that turned out to be! There
I was expecting to simply confirm taxonomically what I had come to know as
D.h. var.hirtella and D.h. var.lutescens by visiting their type location and
the first thing I stumble on was something which looked more like a cross
between both taxa! The rosettes were wine-red, the scapes ascending, colored
yellowish except for the base which was reddish, and covered with red hairs.
What was it? A new taxon? A hybrid? Or could I have been wrong all those
years and THIS was the true D.h. var.lutescens? Not knowing what to think of
these plants, I called them D.sp."Corumba", since I found them growing by a
waterfall of this name at the Serra dos Pirineus.
Later that afternoon, I hiked up a hillside a few km away and suddenly
stumbled (with relief) on a populations of (THANK GOD) normal-looking
D.h.var.hirtella with green rosettes, wide cuneate lamina, strongly
ascending blood-red scapes and covered with equally colored hairs. OK, so at
least that one I'd apparently gotten right over the past few years. But
then, walking a little further on I spotted more compact wine-red colored
rosettes, the leaves narrower, lamina not as distinct from the petiole, the
scapes very thick, bright yellow in color, and covered with larger
whitish-yellow hairs. It was D.h. var.lutescens! And it was growing mixed
with D.h. var.hirtella, with no signs of any morphologically intermediate
plants. So for a few minutes I was sure that D.sp."Corumba" was indeed a new
taxon, the fourth in the D.hirtella-complex. But only for a few minutes.
Circling around back towards the car, I found more hirtella and lutescens
as well as D.sp."Corumba". And even worse, I found some specimens with
ascending scapes covered in white hairs and others completely red with red
hairs on slightly ascending scapes, not matching any of the four
D.hirtella-complex taxa I'd previously identified. What the hell was going
on here?!?! A taxonomic equivalent of an orgy?? At times like these I almost
feel like stomping such taxonomic quacks deeply into the surrounding black
muck and pretending I never saw them! Well, the sun was blistering hot, I
was sweating like a pig, I had little time left to enjoy Brazil before
returning to Japan, and I'd been on the road too long already and was
physically exausted. As you can imagine, I wasn't therefore exactly in the
right state of mind to deal with such a complex taxonomic puzzle. So I just
turned my back and headed on home to S.Paulo, leaving the Serra dos Pirineus
and its mysterious Drosera for a future exploration.
Since that trip in March 1997, I'd been dying to return to the Serra dos
Pirineus and hopefully unravel the taxonomy of the D.hirtella-complex, if
this was at all possible. So when my friend told me she would be getting
married in Brasilia in April (a good time to catch cerrado CPs in flower)
1999, I knew what I had to do. In fact, while most of the CP hunting on this
trip was done after the wedding, I actually stopped at the Serra dos
Pirineus before going to Bras\355lia. I just couldn't resist, I was too eager
to find out what was going on there.
After leaving S.Paulo, we spent our first night at Goiania, capital of
Goias, and in the morning, before heading north to the Serra dos Pirineus, I
checked out the herbarium at the Federal University of Goias, where I ended
up obtaining lots of excellent location data which I would later use to plan
the route of the trip through Goias (together with more info from the
University of Brasilia herbarium). Anyways, we arrived at the Serra dos
Pirineus in the afternoon, explored around the town of Pirenopolis (a lovely
colonial-style town where we spent the night), in the morning crossed over
the moutains to the town of Cocalzinho, and then briefly checked the Corumba
waterfall. I don't know off the top of my head how many CP species we saw on
the S.dos Pirineus, but it was a LOT! Best of all, I think I was actually
able to solve the D.hirtella-complex puzzle!
You know what it was that was causing most of the confusion? A natural
hybrid! No, it wasn't hirtella X lutescens, but *COMMUNIS* X lutescens!
Strange, huh? The rosettes were sometimes flat like in D.h. var.lutescens
and sometimes semi-erect like in D.communis. The pinkish or reddish-green
leaves had petioles more clearly distinguishable from the lamina than in any
D.hirtella-complex taxon. The scapes were also reddish and strongly
ascending and covered with white hairs. Funny enough, the scapes often
showed a touch of hybrid vigor, being robust, tall, and producing a large
number of flowers each. These were lilac in color and the fruit were
sterile. The sepals were also large, narrow like those of D.communis.
I wasn't too sure it was a hybrid though, especially because there were
other Drosera present which could act as potential parents: D.h.
var.hirtella, D.sp."Corumba", and also D.montana var.montana. But proof came
from two other locations where I saw this hybrid further on in the trip. One
was at Mineiros in SW Goias, where other than D.communis and D.h.
var.lutescens there was only D.sp."flat red" around. The other was at the
Serra Dourada, where only D.communis and D.h. var.lutescens were present.
Although this hybrid is now straightened out, D.sp."Corumba" is still not
as clear in my mind. Although I have no doubt it is truly a good taxon, I
still have to learn to diferentiate it better from D.h. var.hirtella. It
seems to be somewhat variable in relation to color, sometimes overlapping
the range of D.h. var.hirtella, so I have to find other characters like
flower details, seed shape, or hair distribution on scape which may help
separate them more easily. The curve in the flower scape is usually not as
strong as in D.h. var.hirtella, but more accented than in D.h.
var.lutescens.
Because color has been one of the main characteristics I've used to
differentiate between these four hirtella-complex taxa, I've found them very
difficult to distinguish in herbarium specimens. Also important is the
distribution and types of hairs on the scapes and whether these are
ascending or not. Unfortunately herbarium specimens are often flowerless or
just too beat-up to be of much use, especially if one considers that there
are always exceptions to every rule which even in the wild may be confusing.
For example D.h. var.lutescens occasionally has strongly ascending scapes
like D.h. var.hirtella or erect scapes like D.sp."white hirtella".
Curiously enough, although both D.h. var.hirtella and D.h. var.lutescens
are variable throughout their respective ranges, including within
populations, at the Serra dos Pirineus both these taxa are surprisingly
unvariable and represent opposite ends of their respective spectra of
variability. The Serra dos Pirineus is the only place I know where both
these taxa occur sympatrically, so it appears that they are doing their best
to avoid any morphological overlap (and therefore competition) by staying as
different from each other as possible. So it seems that St.Hilaire
accidentally chose the perfect place to collect type specimens for these two
taxa.
We found some new D.h. var.hirtella sites around Brasilia and discovered
that it is very abundant in the new areas we explored in NW Minas Gerais,
where we discovered the lowest site (in altitude) I'd ever found for this
taxon: around 525m. At one site near the town of Unai (a large and beautiful
vereda with many buriti palms spread over a wide grassy hillside seepage) we
saw a surpisingly wide variation in rosette color, from all green to a very
dark blood-red, maybe even somewhat purplish. We also saw D.h. var.hirtella
in E Goias, around the town of Cristalina, at one site growing sympatrically
with D.sp."white hirtella" (both easily distinguishable from each other).
Therefore the range of D.h. var.hirtella appears extend in the E from the
Serra do Caraca in central Minas Gerais all the way N along the Espinhaco
Range to Catoles in S Bahia, and in the W from Cristalina N through the
Serra dos Pirineus and Chap.dos Veadeiros, probably growing N along the
highlands between Tocantins and Bahia, possibly even reaching into Maranhao
and Piaui states.
As for D.h. var.lutescens, we found it at several locations from central to
S Goi\341s, including right near the border with mato Grosso do Sul, where it
probably occurs not only in the N part of the state, but maybe even in the
highlands extending S along its center. I know the range of D.h.
var.lutescens reaches W to the Chapada dos Guimaraes in S Mato Grosso, but
don't know how much further W and N it goes from there, since those parts of
the country are still very unexplored. Considering the altitudes, I think it
may be present in the N part of Mato Grosso and probably extends into the
state of Rondonia and maybe even in neighboring Bolivia. In the SE, it is
know to extend into SW Minas Gerais and N S\343o Paulo.
D.sp."Corumba" is so far only know from the Serra dos Pirineus and the
Serra Dourada in central Goias while D.sp."white hirtella" is only know from
E Goias and the Federal District. Could the former maybe be of hybrid
origin, originally a hirtella X lutescens cross? Maybe it's a case similar
to that of D.anglica, where the hybrid is sterile but after the chromosome
numbers are doubled it became fertile. The only problem is that D.h.
var.hirtella and D.h. var.lutescens apparently do not hybridize, so if it is
of hybrid origin, than it may have occured a few thousand years ago before
the two taxa diverged so much as to not even produce sterile hybrids.
So some may ask why D.h. var.lutescens hybridizes with
D.communis and not
with the rest of the hirtella-complex. Well first of all I already had
chromosome and DNA sequencing results to support that the communis and
hirtella-complexes were closely related, so it wasn't too much of a
surprise. Maybe D.h. var.lutescens represents the basal taxon, the
most "primitive" among the hirtella-complex taxa. But what IS strange
is that it hybridizes with D.communis in Goias, but not at the Chap.dos
Guimaraes. I guess this just helps support a previous hypothesis of
mine that the D.communis from the Chap.dos Guimar\343es are truly a
separate taxon, what has previously been described as D.communis
var.alba.
UFA! Enough of this endless taxonomical-Drosera-high of mine, huh? Next
come Genlisea and Utrics....
All the Best,
Fernando Rivadavia
Sao Paulo, Brazil
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