Unknown rockpool (Algae?)

Post by **MWP admin** » Mon Nov 06, 2006 10:33 pm

At first glance taught to be Zannichellia but this formed regular whorls of many leaves (resembling some Equisetum), rather than opposite pairs, so its not Zanny. Probably an algae.

Q: Does Malta have Zannichelliea melitensis as the only Zannichelliaceae member? (ie no Z. paulistris too?)

valerandi · Post by **valerandi** » Tue Nov 07, 2006 9:45 am

Yes its a Chara species, one of the few good looking algae. It sometimes becomes whitish because it deposits minerals on the outside hence the name stonewort.

You also have Callitriche truncata in the background.

Can you tell me where you found the pool?

thanks

regards
Stephan

jackpot · Post by **jackpot** » Tue Nov 07, 2006 3:40 pm

yes, I confirm valeri- Chara is not rare, e.g. we found it in rock pools of Ta`Cenc as well as the area of Nadur Tower, at the top of Wied Incita a.s.o.

jackpot · Post by **jackpot** » Tue Nov 07, 2006 3:42 pm

btw: Chara is the most important algae (for this forum

) because it is the mother of the mosses (and also for the higher plants)

valerandi · Post by **valerandi** » Thu Nov 09, 2006 9:41 am

I've also seen a large meadow of Chara sp in the running water of one of the pools in the valley below Targa gap and at mtahleb valley.

I'm not sure if its the same species.

regards

Post by **MWP admin** » Thu Nov 09, 2006 6:05 pm

Thank you guys for all the precious info. This forum cost me a hack of time and problems with spam and robots, but at least I learn some Maltese botany fast and with pleasure. Hope the interess lasts long, because the Maltese attitude of higher authorities makes life difficult for most naturalists / environmentalists / biologists.

Anyway,
This pool was found at Lapsi, and was about 70cm across. There were not much pools around and I do not now how this pool survived this warm and arid October + November.

- - - - - - -
I am afraid global warming is really over us. Usually September till end November gives 320mm or rain, and we have only 160mm.

valerandi · Post by **valerandi** » Wed Nov 15, 2006 9:08 am

Re: Callitriche truncata

Its the only Callitriche to be found in Malta that has transparent submerged leaves, no terrestrial leaves and is normally restricted to rock pools in coralline garigue. There are said to be four or five more Callitriche spp. in Malta.

Its said to be frequent but considering (1) the small number of suitable pools that are left (it is found in pools that do no not dry out rapidly) (2) That it is not found in all of these pools (Its not usually found with Zannichellia) I believe it should be classified as rare.

The interesting thing about this plant is that its flowers are submerged, fertilisation and fruiting are underwater (as are Zannichellia's) so its completely aquatic, which is fascinating considering the surrounding rocky garigue the pools are found in.

regards
Stephan

Post by **MWP admin** » Wed Nov 15, 2006 5:48 pm

Yes, good observation in fact. I dont know if I understood your point well, but you are wondering how does a strict aquatic small plant like callitriche truncata is able to disperse to other pools far away ???

valerandi · Post by **valerandi** » Fri Nov 17, 2006 9:26 am

Dispersion of seeds is by wind I believe. What I find interesting is that submerged pollination is employed by marine sea grasses which are to deep to have aerial pollination. Why does this happen also in shallow rock pools? Most aquatic plants still employ areila pollination.

I think it may have something to do with the fact that the pools are in fact so isolated. This means that the ability to self fertilise would be important (Its important in the crustacea that live here anyway). And if one is to self fertilise why stick up a flower into the air?

regards
Stephan

IL-PINE · Post by **IL-PINE** » Fri Nov 17, 2006 2:45 pm

Well these pools I think dry up in summer. The wind can easily disperse seeds on the little base of the pools hux.

Sdravko · Post by **Sdravko** » Sat Nov 18, 2006 7:27 pm

well, algae are very primitive plants (but chara is the most advanced genus) and what is more important they are predominantly water or wet location plants. the sexual reproduction of algae can be very complicated but it usually includes swiomming "sperms" which might look a lot like human sperms so they are adapted for swimming but not for flying.
all the sea grasses or the rockpool spermatophytes are derived from wind pollinated land plants so they will do aerial pollination whenever possible.
(eeeh...to put it very simplistic)