Azolla
Azolla WPP2016 - Week 35 - Leaves +Ken Fowkes, Alen Ianni , Tim Kennedy , Robyn King , Rob Masters , Bernhard Rembold , Byron Sheldrick , Francesco Scaglioni , Alicia Smith , Grandma Snyder , Navin Upendran and Mary Wardell #WPP2016 #WPP2016-Wk-35-Leaves Azolla pinnata (probably) in macro, a sort of floating fern noted for a symbiotic nitrogen-fixing bacteria, which is what gives the red colour. Actual size is 4-8mm long.