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re: E. horemanii

To HAK from Brisbane,

Thanks for the interesting information about E. hormanii!

<hak at ozemail_com.au> says:
>I grow three variations of this sp;the green form,red form(var PISCES),red 
form(var Victoria)

I had not previously heard about two red forms of hormanii. Can you share
the source (aquarium magazine article? plant catalog?). Were the horemanii
varieties named in Australia?

>Red form(var PISCES)
> Leaf shape is unlike E. H (green),closer to E. Uruaguansis i.e long         
> straplike(600mm)

According to the latest information - the 1994 Haynes/Holm-Nielsen monograph
on THE ALISTMATACAE,  E. horemanii is now listed as a synonym to
uruguayensis. This treatice tends to do more lumping than splitting, to
recognize the geographic variability in species and the lack of good
documentation on all collected specimens.  Other synonyms for this species
are martii, osiris and barthii which are all very different looking plants.
Although this approach may be scientifically valid, I do not think it helps
aquarists talk about their plants which have different appearance and
possibly different growing characteristics.  I also note that Rataj's
earlier classification differentiated horemanii as having a wider leaf, but
he had a category "11b" of narrow 30mm wide red leaves which he called E.
uruguayensis!

>Optimum growth at 20-25C (our southern winter;8hrs of light)
>I. Cold water species (15 to 25c)

This makes sense, since it comes from southern Brazil (near 25th - 30th
parallel +/-). Interestingly, this is very similar to Brisbane!! In the TFH
book, AQUARIUM PLANTS, Rataj and Horeman (after whom it is named) say that
in nature, it often grows in cool water. I believe it also flowers during
the winter in Florida, USA, which is at similar latitude.

> This is the KEY TO REPRODUCTION

You also point out that it does best during the short winter day. Since the
plant comes from subtropical (or temperate) area, it gets a seasonal change
in day length. Apparently, it also needs a SHORT day to flower. Next year I
adjust my artificial lighting to give mine a Brisbane 8-hour winter! 

> Red form(var Victoria)
          Leaf shape is closer to E.H(green);muddy red/brown
          Only plantlets from flower spikes so far

From the description, I must have something similar to what you call var
Victoria. If it is a similar plant, then I assume that your plant to too
young to have a substantial rhizome??

>IV. The red forms are unsuitable for planted show tanks as they DOMINATE

I agree, but they are BEAUTIFUL and I still enjoy them in my crowded
"unshow" tank!
     

Neil Frank                 Aquatic Gardeners Association,  Raleigh NC