A tiny rock pool on the beach (middle-shore) approaching Lower Largo Harbour from Lundin Links. Lots of barnacles and some limpets but my eye was drawn to the centre of the pool where there was a mass of minute blue-grey larval-like creatures (about 3mm in length) that were in continual rapid motion although maintaining the roughly circular shape of the mass.
Looking at the close-up photo (click to enlarge) they are segmented, with antennae and paired legs. That suggests arthropods and crustaceans. (Crustacea is the major group or subphylum of the phylum arthropoda that includes the crabs, prawns, and sandhopper types of animal.) I think that these are very small marine crustaceans of the order isopoda, although I wouldn't like to hazard a guess at the species. The land-based woodlice belong to the same order - they have an ‘armoured’ body or exoskeleton with lots of limbs and joints, and their body is flattened from top to bottom. Can see the resemblance to woodlice in the close-up below.
Update (August 2015) - Thanks for the comments and especially to the person who identified them as marine insects of the order collembola rather than crustaceans, with the name Anurida maritime or seashore springtail.
5 comments:
I've seen these too, in a rock pool at Lizard in cornwall
These are actually insects called Anurida maritima, they are often found on the upper and mid shore crawling around or occasionally floating in groups.
Thank you for all the comments. A special thanks to the last contributor who identified the insects as Anuroda maritime, as I hadn't been able to find them in any of my seashoe guides.
Very nice to get this ID at last - have seen them on Broad Haven beach north and couldn't find them in any of my guides. Now I know what I'm looking for they are there after all - lipura maritima in my book but same thing
Broad Haven in Pembrokeshire west wales
Post a Comment