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There are hundreds of species of shrimp found in fresh, brackish and sea
waters all over the world. Most of these species are very small, some of
them are not usable for human consumption or commerce of all the species,
as per Food and Agriculture Organization of the United Nations (F.A.O.) they
lists 342 which are actually or potentially significant commercially. This
number includes species used for human consumption, species used for
feeding of some other types of fishes, and species considered to have
potential commercial value. Together, landings of these shrimp amount to
some about 1.8
~
2 million metric tons in nearly 100 different countries.
From the 342 we have selected only some species, which are mainly from
penaeidae
family (species that are the main growing in our region – Middle East- indo
pacific ocean that are the most important commercial species.
Figure 1 shows the numbers of shrimp in each family that F.A.O. considers
commercially significant, and the number of species in each family covered
in the list.
Figure 1. Family category of known shrimp
|
Family |
F.A.O. species |
|
Solenoceridae |
17 |
|
Aristaeidae |
8 |
|
Penaeidae |
109 |
|
Sicyoniidae |
10 |
|
Sergestidae |
11 |
|
Nematocarcinidae |
1 |
|
Atydae |
16 |
|
Pasiphaeoidae |
5 |
|
Rhynocinetidae |
2 |
|
Campylonotidae |
1 |
|
Palaemonidae |
82 |
|
Alpheidae |
11 |
|
Ogyrididae |
1 |
|
Hippolytidae |
19 |
|
Proussidae |
2 |
|
Pandalidae |
34 |
|
Crangonidae |
13 |
|
Total |
342 |
Anyhow, due to more similarity in majority of species, identifying of each
species form the others are not easy, even for the skilled and expert
peoples are not so easy to recognize each species from the other. The varied
colors and shapes of shrimp of the same species at
different times and from different areas, and the great complexity of the
species that exists.
Some species can only be differentiated from similar members
of the same family by the shape of the genitals or by obscure distinctions
in the shape or structure of a leg or other appendage. Some of these
distinctions, while important for scientific use and resource management,
are of little interest to the industry.
The
information mentioned here is mainly will give you the general idea about
the differentiation of species and will not give you to identify
scientifically every shrimp species. To understand better identification of
many species requires considerable experience as well as expertise. So you
have to refer to academic and R&D department of the fishery authorities and
Alosto the sources of F.A.O. or to a lot of books which been published in
this issue.
At
this illustration we only intended to give an overview of the major
distinctions between the commercial shrimp species of
Penaeidae
that is included.
Colors of shrimp present a similar problem. The color illustrations in this
site represent the shrimp as accurately as possible. But shrimp colors are
enormously variable. When alive, most shrimp are basically translucent, with
rather pale tints. The colors intensify after death. The colors also change
colors vary considerably, as do shapes, sizes and many other features.
Scientific literature will report a species as having.
How
usually shrimp are classified
The
biological hierarchy, which applies to all living things, not just to
shrimp, is shown in Figure 2.

The
biological hierarchy as it applies to shrimp is shown in Figure 3.
(Click Here to Show Image). All shrimp are within the suborder Natantia. Within
that suborder are three infra orders, Penaeidea, Caridea and Stenopodidea
shrimp. Of these, only the first two have any commercial value. Pandalus
as the first word of the name are members of the Pandalus genus.
The
first major distinction between penaeid and caridean shrimp is
the shape of the second segment of the abdomen. In caridean shrimp, the side
of the shell (known as the pleurum) of the number two segment overlaps the
shells of segments one and three. Penaeid shrimp do not have this feature,
but instead the pleura of each of their segments slightly overlap the one
behind. (see this, in illustrated at Figure 4. below)

Note that penaeid shrimp are a family as well as a super family and
an infra order. Starting from the top, the scientific name for the infra
order is PENAEI -DEA, for the super family PENAEOIDEA and for the family
PENAEIDAE. The differences in spelling
are as slight as many of the differences between related species of shrimp.
from 17 commercially significant families of shrimp, most commercially
important species belong to only four: the penaeidae, pandalidae,
crangonidae and palaemonidae. And from these families, penaeid is, obviously
a penaeoid shrimp, the other three are caridean shrimp. World-wide, about 80
percent of shrimp harvested are penaeoid, the remaining 20 percent caridean.
Figure 5 (below) shows a typical shrimp with the major parts of
anatomy labeled. But still you must keep in mind that these are only the
more easily recognized pans. The many parts used by taxonomists to identify
shrimp include a number that can only be inspected properly under a
magnifying glass


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