Water crowfoot ID

[rscott74]

These are 3 images of what I assume are Water crowfoot which, according to Rose, are difficult to ID. The plants were growing in a pond with no inlet or outlet but with fresh looking water. From the illustrations in Rose, rather than the text I think it's Stream Water crowfoot. Can any one confirm please?

[Tormentil]

Is it Brackish Water Crowfoot - Ranunculus baudotii.

I got one in a small pool at Messingham the other day. This pool too had no inlet or out let.

[Tiggrx]

There's not really much chance of IDing this from the picture. Stream Water-crowfoot rarely grows in ponds, prefering fast-flowing streams. Your plant would most likely be either Thread-leaved Water-crowfoot (Ranunculus trichophyllus), Common Water-crowfoot (Ranunculus aquatilis) or Pond Water-crowfoot (Ranunculus peltatus). They are best separated by comparing the shape of the nectary.
If you are going back to look at the plant you coukld try picking off a petal and looking for a small pit in the yellow part of the petal (you will need a hand-lens). You need to see whether it is crescent-shaped (R. trichophyllus), round (R. aquatilis) or pear-shaped (R. peltatus or R. penicellatus). This can often be quite difficult to see, and also difficult to decide on which shape it is.
Not an easy group to get to grips with!

[Tiggrx]

Originally Posted by Tormentil

Is it Brackish Water Crowfoot - Ranunculus baudotii.

Sorry forgot about that species. This one grows near the sea (I'm rarely near the sea so forget to consider it). It has crescent-shaped nectaries and differs from R. trichophyllus in having petals touching (which makes your plant not R. trichophyllus having looked at the pic again)

[Tormentil]

Have I mis-ID'd mine then? I based my ID on other pics in the Gallery.

[rscott74]

Thanks Tormentil and Tiggrx. I'll go back and have a better look, it's only 10 mins walk from home. I've got a 8x/15x lens so I'll have a closer look as sugested. I've also been able to place the 8x lens in front of the camera to give enhanced macro but with difficulty focussing because of the fixed focal point. If I can get a relevant image I'll post it.
I did go back today and lifted some for my fairly new wildlife pond - are they likely to thrive and/or be useful? I planted them in a seed tray in a mixture of clay, fine soil and sludge from our fish pond. At present they a fairly sorry sight and wouldn't be good for investigative purposes.

[rscott74]

Took this picture today. The nectary looks pear shaped to me, therefore Pond?

[Tiggrx]

Originally Posted by rscott74

Took this picture today. The nectary looks pear shaped to me, would you agree and what does that make it, in English?

If it is pear-shaped (which I think it is) then it would be Pond Water-crowfoot (Ranunculus peltatus) - one of the commoner.

The only thing that slightly bothers me is that I can't see a top end to the nectary (and I have enlarged your pic), so it may be a very deep crescent shape...

[rscott74]

Thanks again Tiggrx. I took an image against a measure and the single petal is 1cm+. The Thread-leaved would be 1/2 that size according to Rose which would settle it as Pond. I appreciate the ID tips which aren't given in my reference book.
As I mentioned earlier I have planted some in my pond - are they likely to thrive & will they be of any benefit?