u - Utricularia viscosa

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This plant is Utricularia viscosa from section Foliosa wich I found 2012.
I'd like to thank Paulo Baleeiro, PhD, Brazil, who identified this plant.
He's studying the U.amethystina complex and the phylogeny of section Foliosa.

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I'm awaiting more informations, and will publish more pictures of this plant 
as soon as it's growth season will begin (year 2012 it was between march to april)

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2 stations only of U.viscosa are known in French Guyana according to Hoff & Cremer's list from 2004.

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The plants pictured here are from a  3rd station

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The plants grow in a depression of a flooded savana.
Little, natural drainage streams guide the water to the lowest parts of the savana.
The ground there is made of very thin clay and very thin white sand particles.

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During the hot season, these areas are completely dry,
and need to be filled with water before new colonies of aquatic/semi-aquatic Utricularia can develop.

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This occur during the rainy season : 
water average is 3750 to 4000mm of rain per year in the plants station's area.

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These two pictures have been taken 22 march 2012 - Water level was 30 to 50cm

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14 April 2013 :  I visited the station, but there was no U.viscosa to see,

                       nore any other aquatic/semi-aquatic Utricularia. 

Other plants :   a small colony of U.pusila, and some very few U.hispida. No Drosera.

Water level :    10cm in the natural canals of the savana, less than 5cm between the grasses.

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12 May 2013 :  I visited the station again, but again there was no U.viscosa to see

                       nore any other aquatic/semi-aquatic Utricularia...

                       It have rained a lot, but the plants need to grow first it seem.

Other plants :   a big colony of U.pusila, and some very few U.hispida & U.subulata. Very nice U.nana, 

                       the tallest corolla was 8mm in diameter. Some U.guyanensis. No Drosera.

Water level :     70cm to 1m in the natural canals of the savana, 10 to 20cm between the grasses. 

                       The water temperature was very high, I could feel it through my boots. 

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30 May 2013 :  It have rained a lot since 2 weeks : we had overflooded areas in our city, and more than 182mm of rain on a single day !

                      There are certainly some plants from different species now - I'll visit the site within the next days.

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02 June 2013 : I was at the biotope but found no U.viscosa : I hope I'll see this plant this year ! 

Other plants :  I saw many U.guyanensis, a colony of thousands of plants, U.nana, very few, 

                      U.juncea and U.myriocysta in small amounts, some U.hispida

                      also a very big colony of U.subulata in full bloom, but still no Drosera in this biotope.

Water level :    70cm to 1m in the natural canals of the savana, 10 to 20cm between the grasses.

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30 June 2013 : This time I was lucky ! Within 1 month, the plants have grown, and they are now replacing the U.subulata colony 

                         I found during my last visit. I found dozzens of plants, and the colony is very extended : it cover nearly 70%

                        of the savana in wich they live  ! 

Other plants :    I found Drosera capillaris for the first time. The other plants I saw are : Utricularia subulata, nana, hispida, guyanensis

                        juncea, and miriocysta. I didn't found any U.pusilla, wich is rather strange.

Water level :     50cm in the natural canals of the savana, 15cm between the grasses.

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On the picture we see healthy looking U.viscosa growing together with U.subulata, 

wich are being replaced by them.

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Here are some more pictures : we see that the plants grow only in the flooded parts of the biotope, 

at the very same places as U.subulata do : the biotope is free from other plants, there is no shade given

by the grasses : the plants grow in full sun only :

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I discovered why these plants are calles "viscosa" , wich mean viscous : when you touch the slender

raceme, you'll feel that it's sticky. The raceme is covered with a slimmy substance, wich is produced

by specialized ceells, but the function of this slimmy area is unknown.

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Maybe it is a kind of protection for the plant, to protect the seed scapes from predators ? 

The shinny appearance of the stem can be observed on the second picture from this page.

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Here are some more pictures of this plant. I visited the site on the 7th of July, and explored the entire area.

In fact, this colony has a greater extension than I thought at first : it covers nearly ALL the savana. 

The plants appear to have a rather fast growth capacity, and on some places on wich I didn't saw any plants

a week before are now covered with houndreds, thousands, or more plants !

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These plants profit of the good conditions wich they have to conqueer new territories, and to protect themselves

from predators, they have developped a rather strange strategy...

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Here are some pictures, wich I shot just after sunset :

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The plants are covered with moisture, wich has been deposited during the night. 

At the time I shot the pictures, the sun was not too hot, and the plants didn't have the time to dry.

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The plants are wet, they are entirely covered with water droplets, as we saw on the pictures.

But : this is not a hint for the plants to deploy their strange ability to protect themselves from predators !

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The fact is that the sticky substance wich covers the entire plant is working very well,

also under wet conditions !

And the reason why the plants are covered with this strange and sticky substance can be seen 

on the next pictures :

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Did you see it ? The plants captured some hungry grasshoppers !

Here it is :

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It seem that these plants developped a mecanism to protect themselves from predators by catching them !!!

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It is incredible  : the power of the glu is so strong that it is impossible for the insects to flee...  

As I tried to loose the hoppers free, I was unable to do it properly...their legs were attached to the plants  

as if they are part of it, and if I cant loose them free, how can they do it by themselves ? it seem impossible !

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Now, the questions are the following :

1) is this plant able to catch aquatic preys ? it seem that it is (a wet plant can catch a grasshopper, as we saw it)

2) are there some specialized cells on the surface of the raceme, like trichomes, wich have the ability

to absord the animal's nutrient substances ?

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I hope that my further investigations will find an answer to this interesting question.

All my discoveries about this theme will be published here as soon as I get the answers to it.

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