Maltawildplants.com is now considered an online flora of the Maltese islands, portraying more than 900 species of plants found in Maltese habitats. It harbours a forum created in 2005 were memberes discuss topics about the Maltese flora and ID of plants.
The flowers are formed within a membranous, saclike spathe (open at top only) inside budding pouches.
Wow, beautiful pictures. I will certainly ask you to illustrate my Lemnaceae paper. Unfortunately, Argotti reports that most of my Lemnas died during the summer.
I have some 10 other photos to choose from. Permission granted on the usual request of an acknowledment caption in the paper (and a copy of the paper for my library if possible!)
Note that I did not receive any email - hope it was not killed by my spam shredder
Can you please illuminate me as to how you managed to identify this one - what makes a root of Lemna any different from the roots of many other plants that are not hydrophytes?
ok, pretty easy to answer: almost 40 years experience with plant morphology! This root is not branched: a monocot! No hairs and no soil particels: Not an terrestrial monocot but an aquatic plant! Very long and thin (only Lemna or Spirodela)! Singular per frond (the distance to the other root in the pic shows that this one comes from another frond or plant: Lemna!
But I can understand your question very well! I ask in the same direction my kids how they are able to know (and to remember) all the different terms and order/commands/instruction they need to setup my PC (and they had no 40 years...)
Thanks very much - a very clear explanation indeed 40 years experience in plant systematics seems to give far better results than going around the countryside looking for nice, big, showy, fancy plants
actually, this is quite a difficult plant. i used to think for months its Lemna turionifera until some of my cultivated plants sprouted several roots per frond. since than i think some turions of spirodela mioght develop very slowly in Malta and might mimic Lemna for months before turning miraculously into spirodela.
Moment moment... I was sure that this is Lemna minor. Is it / could it be something else ??
Question: In the second photo, left side, there is a purpulish budding like growth? What is that? Asexual reproduction by budding or some membranous flower?
definitely not Lemna minor. but Lemnaceae are a notoriously difficult Family. why do you think im studying them? The purplish thing might be a new frond.
as i promised you you will get the opportunity to photograph all samples i have and you can post them if im ever able to identify them.
ok, pretty easy to answer: almost 40 years experience with plant morphology! This root is not branched: a monocot! No hairs and no soil particels: Not an terrestrial monocot but an aquatic plant! Very long and thin (only Lemna or Spirodela)! Singular per frond (the distance to the other root in the pic shows that this one comes from another frond or plant: Lemna! 
40 years experience in plant systematics seems to give far better results than going around the countryside looking for nice, big, showy, fancy plants 