There is the various size of the carnivorous plant, but there is a carnivorous plant that does not look like one due to its tiny size and hidden preying mechanism. This species of Utricularia is under the family of Lentibulariaceae and native to North America. Commonly known as bladderworts, it was virtually unknown except to specialists such as aquarium hobbyists due to several reasons. They are always found in very wet areas or in the water area where it is quite challenging to locate the source due to their tiny size.
Among all the carnivorous plants, apart from Aldrovanda vesiculosa, this bladderwort has no root but branches in the green or brown stem which is 0.1 to 3 millimeters in thickness. The green branch arises finer green branches in whorl arrangement that further divide into almost feathery in which usually bears tiny bulbous traps. Some species are running on the mats with green leaves at different sizes without stem with bulbous trap beneath the leaves that generally found underground. The green leaves have a photosynthetic function that produces food for this carnivorous plant.
Interestingly, this carnivorous plant can be either aquatic or terrestrial plant. It has the capability of growing at biphasic habitat which is an advantage for it to survive in specific areas such as pond that partially dry out in the summer or areas where there is flood during rainy seasons. The former is found as strands, mats, or carpeting plants which can also be floating in quiet, acid ponds, bog-associated waters. To grow as a terrestrial planet, it has to grow at the condition that is damp, sandy, acidic soils with the main plant parts at or below ground level. It is considered primarily aquatic although a few are terrestrial, most of them live with the catching and dining lives in water.
It can be quickly growing on sphagnum moss mats, hammocks, and lava rocks which are quite wet sometimes. Cultivation of Utricularia has to be a very wet condition that prefers strongly acidic conditions. Extra care must be taken as they are easily attacked by fish and snail which then become quickly overgrown with algae. The reason they are adapted to strongly acidic conditions is to avoid the attack of fish and snail which are unable to survive in strongly acidic conditions.
Since both Utricularia and Pinguicula are members of the same family, their inflorescence is quite similar. However, it does not produce flowers all the time but occasionally depends on the growing conditions. When it is cultivated as an aquatic plant that is fully immersed in the water, no flower will be observed. On the other hand, if it is growing as a terrestrial plant, it eventually produces tiny flowers that have various colors mainly purple, pink, and yellow which have very thin but supportive flower stalk. Certain species which grow just beneath the water surface will produce flower which blooms above the water surface—this known as aerial flowers of Utricularia.
The propagation of this genus of species is usually through the growing stolon or creeping stem that gives rise to new plantlets. Although it has flowers, the design of the flowers does not seem “welcome” to the pollinators as the floral structure is structured in a way that is away from the potential pollinators. However, scientists found that there are still some seeds for certain species from the unpollinated flowers, perhaps it is self-pollinated. This Utricularia sometimes floats or sinks to the bottom of the stream or pool.
Then, how does this tiny trap the prey? And what are their targets? Ants? Although it is small, it is fast and having a complex trapping mechanism. The preying mechanism is only visible with the help of specialized photography or videography with the slow-motion editing on the videos of the preying mechanism. It has traps that look like small bladders with a small opening on each trap. The opening is guarded by a larger, upper-hinged veil of plant tissue which referred to as a door. The door is weakly sealed against the casual entrance by a thin layer of mucilage which is supported by a smaller veil of tissue, the velum. The trap has two glands namely, minute glands on the surface of the trap and peculiar quadrifid glands located on the interior walls of the trap. The velum, sealer of the trap, functions to create the difference in pressure in which negative pressure inside the trap.
When there is a stimulation of the hairs around the opening by the prey (microorganisms such as water insects, protozoans, tiny crustaceans, and rotifers or mosquitoes larvae sometimes), the stimuli causes the relaxation of the velum thus free the opening of the entrance. The series of actions caused the suction force to develop. The prey is then entered into the trap with the inrush of water. There is no escape because the door is hinged. About fifteen to thirty minutes later, the trap recreating the negative suction pressure within it again. The prey is digested with the help of digestive enzymes produced by the quadrifid glands for a period of several days. It is possible to catch or prey on multiple victims before the previous one is completely digested. The reason it called the fastest carnivorous plant is that the entire trapping speed of this species has estimated at 1/460 second as compared to other slow-motion preying mechanisms of other carnivorous plants.
Since this species is exceptionally tiny to be noticed in nature, how do we source it at the beginning? Well, some nurseries and garden centers do sell Utricularia primarily those are targeted to carnivorous plant hobbyists and collectors. One also can join specialist societies in Facebook groups for species and information exchange. Species such as Utricularia graminifolia is commonly cultivated as an aquatic carpeting plant due to the high-density growing property. Interestingly, this bladderwort sometimes “behaves” as a vegetarian by accident. The small waterweed Wolffia sp. which commonly known as duckweed has been found entrapped in the larger bladder of Utricularia macrozhiza vulgaris which was found ingested when the trap was accidentally sprung and not because Utricularia has gone vegetarian.
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