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EXECUTIVE SUMMARY: At present, the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) criteria used to assess whether a population qualifies for inclusion in the CITES Appendices relate to (A) size of the population, (B) area of distribution of the population, and (C) declines in the size of the population. Numeric guidelines are provided as indicators of a small population (less than 5,000 individuals), a small subpopulation (less than 500 individuals), a restricted area of distribution for a population (less than 10,000 km2), a restricted area of distribution for a subpopula-tion (less than 500 km2), a high rate of decline (a decrease of 50% or more in total within 5 years or two generations whichever is longer or, for a small wild population, a decline of 20% or more in total within ten years or three generations whichever is longer), large fluctuations (population size or area of distribution varies widely, rapidly and frequently, with a variation greater than one order of magnitude), and a short-term fluctuation (one of two years or less). The Working Group discussed several broad issues of relevance to the CITES criteria and guidelines. These included the importance of the historical extent of decline versus the recent rate of decline; the utility and validity of incorporating relative population productivity into decline criteria; the utility of absolute numbers for defining small populations or small areas; the appropriateness of generation times as time frames for examining declines; the importance of the magnitude and frequency of fluctuations as factors affecting risk of extinction; and the overall utility of numeric thresh-olds or guidelines.

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Phylogenetic relationships among all described species (total of 12 taxa) of the decapoda, were examined with nucleotide sequence data from portions of mitochondrial gene and cytochrome oxidase subunit I (COI). The previous works on phylogeny proved that the mitochondrial COI gene in crustacean is a good discriminative marker at both inter- and intra-specific levels. We provide COI barcode sequences of commertial decapoda of Oman Sea, Persian Gulf, Iran. Industrial activities, ecologic considerations, and goals of the decapoda Barcode of Life campaign make it crucial that species of the south costal be identified. The reconstruction of evolut phylogeny of these species are crucial for revealing stock identity that can be used for the management of fisheries industries in Iran. Mitochondrial DNA sequences were used to reconstruct the phylogeny of the Penaeus species of marine shrimp. For this purpose, DNA was extracted using phenol- chloroform well as CTAB method. The evolutionary relationships among 12 species of the decapoda were examined using 610 bp of mitochondrial (mt) DNA from the cytochrome oxidase subunit I gene. Finally the cladograms were compared and the resulted phylogenetic trees confirmed that the Iran's species origin is Indo-west pacific species. Iran's species, which were not grouped with the other decapoda taxa seem to always form a sister clade with Indo-west pacific species with strong bootstrap support 100%. The result completely agrees with the previously defined species using morphological characters.However, we still lack any comprehensive and clear understanding of phylogenetic relationships in this group.