Sida crystallina is a large (up to 4 mm) and very transparent cladoceran. The trunk limbs they use for feeding and respiration are clearly visible inside the protective carapace. This species uses adhesive anchors (situated on the back of the head) to attach themselves to water plants and other substrates.

 
Part of the Collection of the Water-flea Circus of the Micropolitan Museum © Wim van Egmond