In The Beginning
Adapt To Trap
What's For Dinner
This Is The Life
It's A Venus Fly Trap
Fun Facts
What Does It Mean
Thanks For The Help
The Creator

What's For Dinner?
If you want to see a Venus Fly Trap get its groove on, check out this awesome clip.  Feed Me

Making the Menu

Since the Dionaea muscipula is immotile, it must develop a way to attract its lunch.  One such aspect is the red coloration that intensifies from the sun.  The more rays they catch, the more appealing they are to insects.  Another attractive quality is found in the glands of the trap.  The adaxial surface of of each trap consists of two kinds of glands.

 The first type is the alluring gland (shown directly below).  These glands are colorless and are imbedded within the epidermis.  Located on the outer margins of the trap, these glands produce a sugar with an appealing odor.  These glands are 1/4 of a inch from the trigger hairs.  This distance is important for the conservation of energy.  While an insect is consuming sugar, it activates the trigger hairs if they are longer than 1/4 of a inch in length.  The trap knows that it is large enough to receive sufficient nutrients, so the trap closes.  Any insect smaller than 1/4 of a inch will not activate the plant to close.  By having this feature, the plant will not expend energy on a wasteful prey.


Alluring glands of the Venus Fly Trap
Photo - Carnivorous Plant Dionaea by Makoto Honda

The second type is the digestive gland.  These glands give the plant the red coloration because anthocyanin is present in their cells.  Anthocyanin is a water soluble pigment located in cell fluid.  These cells are much larger and stand out prominently.  (The photo directly below shows these digestive glands). 

Digestive glands of the Venus Fly Trap
Photo - Carnivorous Plant Dionaea by Makoto Honda


Closing Time

The Dionaea muscipula is known from its characteristic trapping mechanism.  In order for the trap to close completely and consume its prey, it must go through four different phases.  To see the whole process take action, check out this amazing clip to see nature at its finest. Venus Fly Trap Takes The Stage

The open phase acts as the appealer because of its red coloration and production of a sugary substance.  In this phase, the adaxial surface of the trap possesses a convex curvature while its marginal spines are directed inwardly.  The  abaxial surface has a concave curvature (photo shown below). 


Venus Fly Trap during its open phase
Photo - Carnivorous Plant Dionaea by Makoto Honda

The shutting phase is the initial closing of the trap, in which the marginal spines loosely interlock.  This closing can take less than a second to occur.  The spines form a cage and remains in this position for the duration of 30 minutes (shown below).  This point is critical for the conservation of energy.  Small insects have the ability to escape between the spines and saves the trap from wasting energy on a small insect.  However, if the insect continues to touch the trigger hairs, the trap will continue to the narrowing phase.

Venus Fly Trap during its shutting phase
Photo - Carnivorous Plant Dionaea by Makoto Honda

The narrowing phase is the closing of the two lobes until they are flattened against each other, with the exception of a small area near the midrib. Nitrogenous bodies cause the flattening of the lobes.
(Shown below)




Venus Fly Trap during its narrowing phase
Photo - Carnivorous Plant Dionaea by Makoto Honda
Venus Fly Trap during its narrowing phase
Photo - Carnivorous Plant Dionaea by Makoto Honda
The close phase is the point when the lobes are completely flattened against each other (shown below).  The pressure is so powerful that the insect's body is crushed.  During this phase the abaxial surface has a convex curvature and the adaxial surface possesses a concave curvature.  All of the digesting occurs at this point. The trap acts like an air tight temporary stomach.  The digestive glands secrete formic acid, which is a colorless bactericide.  This acid drowns the prey if it somehow survived the narrowing phase.  The digestive glands absorb the soft parts of the insect, allowing only the indigestible chitinous skeleton to remain. Digestion peaks at about 3-4 days. The trap remains closed for 1-2 weeks until digestion is completed.  However, if the insect is too large for the trap (more than 1/3 its size), the insect can cope with the closing pressure and subject the trap to bacterial decay.  In about 2 weeks, the trap turns black and dies instead of opening.

Venus Fly Trap during its close phase
Photo - Carnivorous Plant Dionaea by Makoto Honda


The remaining chitinous skeleton eventually falls out of the trap by wind or some other external force.  Each trap is able to catch prey 3-4 times.  After these captures, the trap ceases to function.  In addition, each trap is only allowed  8-10 non-feeding closures before it loses its function.

There are factors that attribute to the speed of the shutting phase.  The older the plant, the slower its speed.  Also, the higher the temperature, the faster the speed.  In fact, at high temperatures, it can shut in less than 1 second with only 1 stimulation of a trigger hair!  This indicates another importance of the sun. 

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