Southern Bladderwort - Utricularia australis
An unusual and interesting floating aquatic carnivorous plant, with submerged flexible branched stems up to 120 cm long but often quite short.
The stems bear little assimilative capillary leaves and other longer leaves with a tooth-edged blade divided into filiform segments. Some of the latter are transformed into bladders (or utricles) about three millimetres in diameter which act as minute traps as well as floats.
The reddish, rigid floral scapes, up to fifty centimetres high, emerge from the water surface so that insects can pollinate the flowers.
The beautiful golden- yellow flowers are arranged in clusters on short stalks departing from the upper half of the scape.
These plants have evolved a simple yet efficient system of catching their prey, for example tiny crustaceans. The valves of the bladder spring open and so create a difference in pressure that sucks the animal inside, then they close again.
The tiny animal is then dissolved by the proteolytic juices and absorbed. Utricularia australis lives in paddy fields, ponds, ditches, even with nutrient rich waters.
Rare but present in northern Italy and Tuscany. Over the past few years, it has not been seen at the Bientina Marshes, Sibolla or Fucecchio Marshes, although a small population has recently been reported at Chiusi Woods.
