ID : Freshwater Algae Species

[Andrew C]

Morning,

I have attached two images showing an algae species growing abundantly in a small freshwater pond at Lower Bruckland Ponds near Seaton on the East Devon coast. This pond is about three kilometres inland of the coast and does not receive saltwater.

Is anyone able to help me out with this one as I have checked all my books to no avail.

Regards,
Andrew.

[Dorts]

Hi Andrew. I'm no expert on Algae, but it's typicaly one of the filamentous 'Bright-green algae's', possibly a Spirogyra sp. There are just so many different kinds of these algae which often require a microscope to split them. Hopefully someone else can be more helpfull.
Dorts

[diggleken]

Hi Andrew,
I dont think, but dont really know, that its a Spirogyra, doesnt quite look thin/filamentous enough to me, but Dorts could well be right. (fence sitting!)
Another shot in the dark suggestion is a seaweed - I know how inland it is, but theres one which can be a little inland and likes brackish and fresh water a bit - Enteromorpha intestinalis - and is the right shape, twisty and bloated.
This is the one that bleaches white when it dies off.
Cheers
Ken

[Andrew C]

Afternoon Ken & Dorts,

Thanks for coming in on this one, I half expected this to be a tricky one. It did stand out to me as looking like seaweed but being inland made me think twice. I shall try to get some samples or someone to look at it if they go there. This will let me see if it whitens as it dries.

It is within a 'private' nature reserve that costs £3.50 to enter and is some way from home! A good spot for Small Red Eyed Damselflies too.

Regards,
Andrew.

[D M John]

Dear Andrew,

Your freshwater/brackish water algae is probably an Ulva (formerly Enteromorpha) if its branches are hollow and tubular. If it were growing in fully masrine conditions or in brackish water then it would be certainly Ulva intestinalis. If conditions are fully freshwater then it is probably Ulva flexuosa. The two species can only be separated by resorting to characters seen by means of a microscope.

Hope these comments are helpful in your quest for a name.

David

Originally Posted by Andrew C

Morning,

I have attached two images showing an algae species growing abundantly in a small freshwater pond at Lower Bruckland Ponds near Seaton on the East Devon coast. This pond is about three kilometres inland of the coast and does not receive saltwater.

Is anyone able to help me out with this one as I have checked all my books to no avail.

Regards,
Andrew.

[Andrew C]

Good morning,

Thanks you for commenting on this one. This was growing in freshwater but I am not sure if I can eliminate the possibility of some saltwater coming in on very high tides. Probably not so it looks like it is possibly Ulva flexuosa but I know this is not certain.

Regards,
Andrew.

Originally Posted by D M John

Dear Andrew,

Your freshwater/brackish water algae is probably an Ulva (formerly Enteromorpha) if its branches are hollow and tubular. If it were growing in fully masrine conditions or in brackish water then it would be certainly Ulva intestinalis. If conditions are fully freshwater then it is probably Ulva flexuosa. The two species can only be separated by resorting to characters seen by means of a microscope.

Hope these comments are helpful in your quest for a name.

David