LESSER BLADDERWORT

Utricularia minor

Bladderwort Family [Lentibulariaceae]

month8jun month8june month8jul month8july month8aug month8sep month8sept

status
statusZnative
flower
flower8yellow
morph
morph8zygo
petals
petalsZ2
stem
stem8round

27th July 20014, Isle of Harris, Scotland. Photo: © Dawn Nelson
The smallest and slenderest of the 7 Bladderworts. The stems are come in 2 types: those which are all floating and which are up to 40cm long; and those which have 4 arms, 2 short and two long (with the long ÷ short ratio between 1.2 to 2). This specimen is not freely floating, so it is obviously of the second type.


27th July 20014, Isle of Harris, Scotland. Photo: © Dawn Nelson
At the top are flowers which have yet to open. The yellow flower is in two hinged parts, an upper lid which attaches to the flowers petiole (stalk) on the top of the lid. The other part of the flower looks a little like a shoe. The lid, shaped like a lavatory lid, seems at be hinged to the back of the much larger lower part of the flower (the 'shoe').


27th July 20014, Isle of Harris, Scotland. Photo: © Dawn Nelson
Your Author wonders whether this above-water part also catches insects, traps them with the lid closing over the shoe, and dissolves them for nutrition (?).


Not to be semantically confused with : Butterworts such as Common Butterwort (Pinguicula vulgaris) although they are in the same family (Lentibulariaceae) and are also Carnivorous, as are Bladderworts. Butterworts grow in damp places, but not in lakes and they do have green leaves which can photosynthesize and roots, so are not totally dependent on insects for nutrition.

Nor to be semantically confused with : Bladder-sedge (Carex vesicaria), Brittle Bladder-fern (Cystopteris fragilis), Bladder Ketmia (Hibiscus trionum), Bladderseed (Physospermum cornubiense), Bladder Campion (Silene vulgaris) or Bladdernut (Staphylea pinnata) [plants with similar names belonging to differing families]

Bladderworts, lacking roots, are unable to obtain nutrients from the lake-bed, so must obtain nutrition elsewhere.

All Bladderworts are  Carnivorous Plants, although they do have chlorophyll in the filigree fern-like green leaves below the surface of the water with which they can synthesize their own products. They obtain obtain other nutrients by the dissolution of insects and water-creatures and their subsequent absorption. Bladderworts are so called because they have tiny flask-shaped bladders along their underwater stems (which are numerous, compoundly branched and fern-like).

When a tiny insect or other creature (such as zooplankton) touches some very sensitive hairs near the opening of the trapdoor on the underwater bladder, this small trapdoor abruptly opens and the insect is sucked in with the entering water. The trapdoor then quickly shuts again trapping the insect within. The insect is slowly dissolved by enzymes or bacteria whereupon the released nutrients are absorbed by the plant. This presumably consists of a lot of nitrogenous compounds which it may not be able to obtain in sufficient quantities from the water. The speed with which the trapdoor opens and then shuts beggars belief - it outpaces the closing of the traps in Venus Flytrap! It happens faster than the blink of the eye uTube video of Bladderwort trap capturing underwater creature. The trapdoor then resets itself by closing and pumping the water partially out of it ready to suck in the next victim (or 'sucker') when the hair-trigger is set off (or'pulled').


  Utricularia minor  ⇐ Global Aspect ⇒ Lentibulariaceae  

Distribution
 family8Bladderwort family8Lentibulariaceae

 BSBI maps
genus8Utricularia
Utricularia
(Bladderworts)

LESSER BLADDERWORT

Utricularia minor

Bladderwort Family [Lentibulariaceae]