U.warmingii - 1st picture know of a rare and unique Utric

[Martin Hingst]

Hi Fernando,

great shots - and a fantastic species! Thanks for sharing Marcos pics -

Martin

[werds]

Very interesting the suppose function for the hollow scape..

One question ,why the utris trap turn black?

[Fernando Rivadavia]

I'm not sure why the traps go black in so many aquatic Utrics. One really interesting hypothesis I've heard is that the traps are actually mini-farms for algae, and that once enough algae are living in the traps, the Utric turns the traps black to kill the algae by light starvation, and then digests the dead algae.

Best wishes,

Fernando

[werds]

Hum yeah , yes already heard about that hypothesis but didn´t know thats maybe the cause for black traps, thanks for the answer!

Edited January 13, 2014 by werds

[LeeBr]

Though it does raise the question of why it has to kill the algae before it can digest them; I would have thought the secretion of digestive fluids into the trap would do the job whether the algae were alive or not.

LeeB.

[Fernando Rivadavia]

Maybe they can't get through the algae cell walls without killing them first? After all, if they secrete enzymes that break down cells walls, then they'd be digesting themselves!! :)

[Fernando Rivadavia]

Oops, double post!

Edited January 14, 2014 by Fernando Rivadavia

[LeeBr]

Interesting; yet if they secrete digestive enzymes they should not work on their own tissues.

Just like toxic animals are immune to their own toxins.

And our own stomachs are not digested by the hydrochloric acid that they contain.

Basically the plant tissues should be able to evolve an immunity to their own digestive secretions; and not have to wait until the prey starts to breakdown after death to digest it.

Unless they are relying on other organisms to break down their prey for them as S. purpurea does.

LeeB.

[Fernando Rivadavia]

Well first of all, please keep in mind that this is all highly speculative right? :)

2nd, we animals have had a little longer evolutionary history of working out our digestive tract "kinks" when compared to any CP group. Maybe Utric traps will some day attain the level of complexity that animal stomachs have in terms of digestive fine-tuning, but maybe they just haven't been able to evolve cellulose-digesting enzymes that do not also attack their own walls - yet.

I've very little knowledge of of cellulases, but I do know that digesting cellulose into simple sugars is not something easy, otherwise ruminants wouldn't need a second stomach for the specialized cellulose-digesting bacteria, and we'd be able to make very cheap biofuels from dead plant matter.

So maybe this is just a simple and evolutionarily cheap way of killing the algae and making them spew their contents. :)

Best wishes,

Fernando

Edited January 15, 2014 by Fernando Rivadavia

[Dave Evans]

I rather doubt the plants can digest the algae. I also rather doubt blackening the traps kills them either, but weakens them to the point they stop globbing up nurtrients before the plant can.

[LeeBr]

Interesting thoughts.

Looks like more experimental study is needed.

Also the space inside the trap and the nutrient supply is limited so the algae cannot keep dividing exponentially forever ; their population would run out of food and crash sooner or later anyway.

LeeB.

[LeeBr]

sorry posted twice.

LeeB.

Edited January 15, 2014 by LeeBr

[Andreas Fleischmann]

Of course Utricularia (and Genlisea) can digest algae (of all kingdoms: diatoms, cyanobacteria, and green algae). But usually living cellular algae protect themselves by a layer of mucilage, which is continuously secreted (both for protection and movement). As soon as the mucilage layer dissappears, the enzymes of the plant can digest the algae. In many auqatic Utricularia (and also in several Genlisea) "algae" (of all organismic kingdoms) even consitute the majority of prey.

All the best,

Andreas

[vraev]

Fantastic pictures. Thanks for sharing. Such unique adaptations. Solutions to the same problem of staying afloat. Amazing.

[Alexander Nijman]

Very interesting that new Utricularia with that unique flooting balloon! And that they could be vegeterian inm some way by digesting algae.

Alexander