Species Archives
Medium name: Long-tailed red dragonfly
Scientific name: Sympetrum cordulegaster (Selys, 1883)
Taxonomic status: Libellulidae of the dragonfly family: Sympetrum Newman, 1833
Typical features: about 40mm in length, male and female color. Males: white in face, brownish green on the compound eye, black spots on the chest, yellowish at the base of the wings, black feet, symmetrical black spots on both sides of the 5-10 segments of the abdomen, slightly protruding on both sides of the seventh segment of the abdomen like spines; females are multi-colored: red, yellow, brown, grayish or yellow, and the long protrusions of the laying valve grow out of the tenth abdominal segment and appendage, and other features are similar to those of males. The long-tailed red dragonfly is more common in the northeast for about 3 months (mid-July to mid-October), preferring to inhabit rice fields and streams, and preferring to have high-falling branches during the mature courtship period.
Adult stage:
Red male
Yellow female
The spawning lobes protrude, and the water is lit on the silt at the water's edge to spawn
Crossover for 10-20 minutes
Egg hatching first molting process:
The egg yellow that has just been laid is put into the water and browned for about 30 days the next day, and a few hundred or thousands of eggs hatch in batches for 10 days, and then hatch sporadically after a month, some of which have entered the final age, and some have just hatched. Immediately after hatching the shell, the first molting began, and after a few minutes the white and transparent skin completely shed and turned away. A second molt begins about 5 days.
Incubation takes about 30 days
The baby worm has just come out of its shell, and the first molting quietly begins
Comparison of the baby worms on the second day of incubation with those that have just hatched
The first to hatch has already molted for the second time, some have just hatched, and most of them are pregnant and waiting for hatching.
This is the case the day after incubation, and the second molting generally begins about 3-5 days after incubation.
At the peak of incubation, some have entered the 4th age, and this is one of the newly hatched.
Juvenile stage:
The second molting begins about 3-5 days after egg hatching. The first three molts do not require bait, and the microorganisms in the water are enough for them to eat. The ability of juvenile insects to adapt to the environment is very strong, not afraid of dirty water, water quality is particularly turbid, the water temperature is 12-29 degrees Celsius does not matter, natural death is rare, usually in the molting is eaten by the same kind, in general, there is enough bait They rarely swallow each other. The amount of food in the first 10 days of the final age has been very large, and then gradually decreased, and the hunger strike began 3 days before feathering, and some hunger strikes lasted for ten days and a half months.
Second molting, compared to the previous age group.
The third molting of the insects compared with the first molting of the insects
Compared with the three age groups, the microorganisms in the water are enough for them to enjoy, allowing them to grow rapidly.
Third molting
The fourth molting, at this moment need to put bait, microorganisms can no longer meet the needs of growth, otherwise they will swallow the newborn little brother and sister.
Fifth molting
Sixth molting with dorsal dotted wing buds
The seventh molt, the wing buds sprout, compared to the previous age group.
Eighth molt
The eighth molt, the wing buds are clearly visible, and the comparison of the three age groups shows that the body will grow much larger with each increase or decrease of one age
In the ninth molt, the wing buds clearly have the appearance of wings and cover the fourth abdominal segment
The tenth molt, the wing buds have a more winged taste, covering the sixth abdominal segment, some growing from wide to narrow over time.
It takes about 50 days from hatching to the end of age, with a total of 10 molts, with an interval of about 5 days between molts.
The mask is open when it is just molted, and then gradually closes. The following image shows how the mask is turned on:
Male feathering
Smooth cardboard babies can also climb up and hold feathers, and all parts of the body begin to swell before breaking the shell, and the head and chest are swollen and hanging first
For about 20 minutes, then quickly reflexively hugged the head of the molt and pulled out the last tail end.
After the whole body comes out, the 4 wing buds that are first rolled together begin to expand and develop. The soft sticky wing buds are like white clouds gathered together and begin to expand in all directions, and at this moment, if seriously disturbed or touched by the external environment, it may affect the development or growth of deformed wings, thus ruining their lives.
It takes more than 20 minutes for the 4 wings to expand and develop
At this moment, other parts are diapause for 20 minutes, and the male U-shaped reproductive organs are prominently exposed and clearly visible.
After the wings have completed, it takes 1-2 hours for the abdomen to begin to develop, and then 4 wings are opened
After the wings are opened, some fly away immediately, and some stay for different lengths, depending on the environment.
Leave the feathering location to find a safer hiding place to hide in case of the unexpected.
Female feathering process
Climbing out of the water is a key step before feathering, and there are many late-aged insects that are about to feather, but they are not able to climb out of the water and die. Originally, the head and back of the picture above should have been almost successful, but look at the following picture to see how serious the problem is. Some of the whole body comes out, but the wings or abdomen are crooked and twisted, which is also equivalent to failure.
The success of feathering is not an easy task, this is not, the above figure is difficult to give birth to new life fixed here. He died prematurely due to the "aortic" cut through the edge of the hard shell that was split by molting. The phenomenon of death during the growth of young insects is rare, and the phenomenon of feathering unsuccessfully halfway through at the most critical moment abounds, so it is more difficult to record the complete life of a single dragonfly than to ascend to the sky.
Although the number of losers does not affect the overall situation, the survival of the fittest is well. Lo and behold, the other group succeeded, although not recording the early process, but without affecting the viewing to continue the feathering process. Success is the strong, and the genes of the strong will be passed on to the next generation.
After the whole body comes out, the 4 wing buds that are first rolled together begin to expand and develop. The soft sticky wing buds began to expand like white clouds gathered together, at first the cloudy milky white gradually grew and covered the abdomen, and then gradually became transparent, the wing veins were clearly visible, and then the abdomen began to develop and grow.
The four wings curled together gradually open until they are developed (taking about 20 minutes), and then it takes about 2-3 hours for the abdomen to begin to grow and develop. The baby insects that are about to be feathered usually start to crawl out of the water in the early morning to find suitable objects (sometimes need to toss for 1-2 hours), walls, stones, grass stems, grass leaves, branches, etc. are all looking for targets, find a suitable place to climb up and grab the six legs, about ten minutes the back and head are split, the head and the front chest are the first to break out of the shell, pull out six feet from the original limbs (if there is a broken foot phenomenon at this moment, it will not grow out), and lean backwards out of the body (it takes about 20 minutes), Wait for the six legs to stretch freely, then quickly reflexively hold the molting head and grasp the end of the abdomen (it takes less than 1 minute). First the four wings curled together gradually open until the development is completed (it takes about 20 minutes), then the abdomen begins to grow and develop (it takes 2-3 hours), and finally after the remaining fluid in the body is discharged, the four wings that are combined gradually open, some of them open at once, and they need to stay for another half an hour to an hour after spreading their wings to fly away to find a hidden place to hide, and the next day they begin to forage. Start a life of dragonflies that leave the water to live and soar into the blue sky.
After 2-3 hours, the abdomen is developed, and the wing veins are clearly visible and the wings open.
After the 4 wings are gradually opened, they need to stay for another half an hour to an hour before spreading their wings and flying away to find a hidden place to hide.