Daphniid ID

[TartanGuppy]

Is anyone able to help identify which Daphniid this is?
This female is about 0.5mm and is mature as has brood pouch & eggs.
Seems to get to about 1-2mm max for adults.
I've been using this guide but feel it takes me down a rabbit warren of similar choices

An Image-Based Key to the Zooplankton of the Northeast (USA)

(I'm in UK so know this is US based)

It just moulted before I attached the camera, the 'ghost' carapace can be seen at the top

 

[dw1305]

Hi all,
Tricky, try: <"Daphnia Collecting">.

cheers Darrel