Date: Fri, 29 Jan 1999 09:51:24 From: SCHLAUER@chemie.uni-wuerzburg.de To: cp@opus.hpl.hp.com Message-Id: <aabcdefg259$foo@default> Subject: Re: Venezuelan Drosera Taxonomy Doubts
Dear Fernando,
> First of all, the division of D.arenicola into 2 varieties is worthless
> if you ask me! I don't have the paper in front of me (at Rolf's), but
> the difference in flower scape length cited for D.a.var.arenicola and
> D.a.var.occidentalis is minimal -- I think up to 7cm and 8cm
> respectively --
up to 2 cm w/ up to 4 flowers for var. arenicola vs. more than 2 cm
w/ more than 4 flowers for var. occidentalis.
> and the difference in flower number ridiculous - - 1- 10
1-4.
> and 4-10
More than 4.
> respectively, I believe. I collected one in Kavanayen - area
> cited for D.a.var.arenicola in Flora of the Guyana Highlands -- which
> had 14 flowers (damn, I just broke one off by accident while counting!).
"More than 4" would include 14.
> Next, D.cayennensis. I remember fotographing what might've been this
> species at Bonn during last year's meeting. It was in the small
> greenhouse full of Drosera (beautiful D.regia, including the albino
> form) which we had to descend to enter. The plants were a pinkish-red
> color with short flower scapes near the entrance, remember Jan? Anyways,
> the type specimen is supposedly from somewhere around Cayenne in French
> Guyana, which is on a coastal plain I believe, where it must be hot and
> stuffy just like the D.sessilifolia and D.biflora habitat I saw just
> north of Boa Vista in Roraima state, N Brazil.
>
> Yet the ones I believed to be D.cayennensis were growing in the Gran
> Sabana in slightly shady habitats at about 1300-1400m. I'm wondering if
> this is truly D.cayennensis because of the altitude difference and also
> because the plants I saw in Venezuela as well as at Bonn (I think, I'll
> have to check the photos I took there - when I find them) had simple
> white hairs all the way up the scape as well as on the calyx lobes.
In this case, both specimens were probably not correctly identified as
_D. cayennensis, which has a glandular indumentum on its scapes.
> The
> description of TYPE D.cayennensis I believe said simple hairs only on
> the bottom half of the scape and glandular ones on the upper half. I
> wonder if there's variation in this character.......
You should compare the seeds with those of the type specimen.
> Now the last doubt regards D.felix and D.kaieteurensis. What is the
> difference between these two species?!?!?! In the brief time I had, it
> seemed like the only difference was that D.felix had a single flower on
> a short scape, almost scapeless while D.kaieteurensis has a slghtly
> longer scape with several flowers. I found several populations around
> the Gran Sabana in areas cited for both species (in Flora of the Guyana
> Highlands and the description of D.felix) with plants that had
> inflorescences as described for D.felix as well as for D.kaieteurensis,
> not only in the same population, but on the same plant!! In fact almost
> every mature plant of this species had flower scapes, most of which were
> single flowered and short. Yet longer scapes with several flowers were
> not uncommon at all.
>
> It seems to me that D.felix is simply based on single-flowered
> specimens of D.kaieteurensis, that is, a synonym of D.kaieteurensis,
> unless anyone can tell me any other differences between these two taxa
> other than inflorescence length and number of flowers.
The two seem to be closely related to each other, indeed. I am,
however, not in a position to recommend a grave taxonomic consequence.
Perhaps your material allows unification of the two.
> And now that I believe I have the real D.kaieteurensis in hands, then
> the one I found on the Serra do Araca' is NOT D.kaieteurensis! What
> species native to northern S.America has spatulate leaves,
> inflorescences glabrous, erect, fragile (not as much as D.communis, but
> nowhere as thick as in D.kaieteurensis). I'll have to check the seeds
Yes.
> since it could be some form between D.capillaris and its possible
> synonym D.tenella, although the plant did NOT look D.capillaris-ish at
> all.
_D. capillaris_ can be tricky sometimes! Be sure the scape does not
even have minute stipitate glands (these are often found in _D.
capillaris_ specimens that look glabrous at first sight).
> Nor D.colombiana-ish.
This should have a hairy scape.
> Maybe D.esmeraldae???
Maybe.
Kind regards
Jan
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:31:54 PST