Looking Into The Life Cycle Of Crustaceans
Ever wondering how you could be able to properly have your crab larvae identification? Crabs, as part of crustaceans, can actually have a lot of larval stages that you have to consider. You must properly identify the characteristics of the crab for you to be able to properly associate it with a specific stage. Crustaceans like crabs really pass from one stage to the other from the moment they hatch from eggs till they are able to reach their adult form. Each of the stage is characterized to be separated by a certain moult. The moult is defined as a hard shell or exoskeleton that is actually removed from the body of the crab as they grow along.
Focusing On Details
Crab larvae identification would not be that difficult as long as you are ready to familiarize yourself with the details. The larval stage of crabs actually resemble that of the adult stage and it can be a little confusing to identify which specific larvae can grow into adults. The key if proper crab larvae identification which can definitely be achieved as long as there is much appreciation and keen observation for details, from the smallest characteristics to that of the largest ones.
The Life Cycle Of A Crab
The life cycle of a crab will actually start with an egg that is known to be fertilized. On the other hand, it can also be caused by parthenogenesis. As this egg is formed and eventually developed, the egg will gradually hatch into a pre-larva or a pre-zoea stage. You will be able to see that the crab is able to pass through different animal stages as it goes one moult after another. This means that it passes through different zoea stages. After the different zoea stages, the larvae would then undergo the megalopa stage also known as the post-larval stage. After the post-larval stage, the crab will further develop into an adult where the creature will continue moulting. You could be able to finally say that the crab is done with its moulting and has finally reached in final form if the gonads are already noticeable and in their actual look.
Looking Back Into The History Of Crab Larvae Identification
You may be thinking how the crab larvae ever discovered. Dated back in the late 1860s, Anton van Leeuwenhoek was considered to be the first man to note the difference between the larval stages of the crabs, generally the crustaceans and that of the adults. He was able to note such by observing the life stages of the crab.
As time passed and as years went on, the scientists became more interested in the study of the life stages of the crabs particularly the larval stage. They have been figuring out how they can properly conduct crab larvae identification and what specific details they could use to do such. There have even been some conflicts regarding the fact that all crustaceans including crabs are undergoing life cycle changes or metamorphosis. Later on, they have disproved such fact because some of the scientists believed that not all undergo metamorphosis and it is only somehow limited to certain crustacean species.
But when the 1870s came, the scientists already resolved the conflicts that they have been encountering and they have already settled on the fact about the final series of larval stages that are actually occurring in crustaceans. This can be considered as the origin of the key to crab larvae identification nowadays. This final series of larval stages was eventually published and made known to the people.
Crab larvae identification may be somehow confusing due to their different larval stages but the key here is to properly understand and define the specific characteristics to be able to make one stage distinct from the other. If you truly make yourself familiar with every stage very well, you can later on rule out the confusion that you can get with crab larvae identification.
The Different Larval Stages of Crustaceans
For the larval cycle of the crustacean groups including crab, the first category would be the branchiopoda. This is considered to be the most basic group of crustaceans. They are considered to be one of those groups without cycle changes or metamorphosis. They only are very much known for their several moults. After each, they are known to have extra parts already in their body without actually changing their total or holistic form.
The second group, the Cephalocarida, is known to have a lot of stages. There are actually15 metanaupliar stages and the known 2 stages called juvenile. This can take a long process before they could finally reach their final form due to the several stages they have to encounter. Every segment is added per stage and this can really take somehow long but you have to remember that this is the distinctive characteristic of this larval group.
The third group is known to be the Remipedia whose larvae is known to be consuming their own egg yolk as compare to groups who use food sources from their environment. This is one of the very famous characteristics of this certain type of larvae. The next group would be the Malacostraca which are known to closely resemble that of the adult stage.
The next larval group is known to be the Dromiacea which is very much influential in crab larvae identification because they fall under this classification. From this larvae, you can truly notice that all crabs compared to other crustaceans in their larval stage share a certain larval form. They are known to share a distinct form known as the zoea which has a curved contour of the abdomen together with a telson that is forked in form. Some of the other distinctive characteristics of this larval for m is the spines that can be found in their dorsal and even in their rostral area.
These are just some of the important considerations when it comes to crab larvae identification. It can be really challenging at first due to the fact that larval stage of the crab can be very comparable to other types of crustaceans but if you will really just put enough attention on the details and if you will just notice the distinct similarity of all the larvae of the crab then as you may not realize easily, crab larvae identification can eventually be easy for you.