They are very unusual looking creatures @Flo54. It would be good if we had a resident entomologist in the community who could identify them for you!
Perhaps @CathM might have an idea - she spends more time in the garden than most people! She also has her own community of gardeners who might have ideas.
Thanks for sharing,
August - last edited August
Mosquito lava see http://www.haslemerenaturalhistorysociety.org.uk/mosquitolarva.jpg and http://www.ozanimals.com/Insect/Mosquito/Culicidae%20family/.html Edit: On reflection I am probably wrong; what size are they?
Anopheles annulipes s.l.