Pakistan Journal of Marine Sciences <p><strong>Aim and Scope</strong></p> <p>The Pakistan Journal of Marine Sciences (Print ISSN 1019-8415, Online ISSN 2710-4583, CODEN PJMSE8) a bi-annual journal is an official publication of The Marine Reference Collection and Resource Centre, University of Karachi.</p> <p>PJMS is dedicated to publish original research papers in the broad field of Ocean Sciences. All the major aspects of marine science are covered in PJMS including zoology, botany, geology, chemistry, physiology, systematic, ecology, physical oceanography and fisheries. The journal is abstracted and indexed by ASFA, BIOSIS, PASTIC, Chemical Abstracts, Current Contents, Oceanic Abstracts and Zoological Records.</p> Marine Reference Collection and Resource Centre, University of Karachi en-US Pakistan Journal of Marine Sciences 1019-8415 AUTHENTICATION AND TRACEABILITY OF PUFFERFISH ‎SPECIES USING DNA SEQUENCING <p>Pufferfish is known a powerful toxin in its skin and organs called Tetrodotoxin. Validation of food authenticity is usually based on the analysis of proteins or DNA sequences. DNA based methods are more effective and can also be applied to different food matrices. DNA barcoding is a rapidly rising global initiative in which species are characterized using mtDNA sequence. This is based on the premise that species are generally well delineated by a species-specific sequence. In this study, we revealed DNA barcoding of three pufferfish species <em>Lagocephalus sceleratus</em>, <em>Sphoeroides pachygaster </em>and <em>Torquigener flavimaculosus</em> using the mtDNA cytochrome b gene region. There were 122 variable and 266 conservative nucleotides of which 110 were parsimony informative over 388 bp sequences. The mean nucleotides composition was found as %28.0 thymine (T), %30.7 cytosine (C), %24.8 adenine (A) and %16.6 guanine (G). Twelve haplotypes were found out of 18 sequences and mean haplotype diversity was observed at 0.9346. This study has strongly authenticated and traceability the efficacy of Cty b in identifying <em>L. sceleratus, S. pachygaster </em>and<em> T. flavimaculosus</em> species with designated barcodes. This is the recorded of <em>L. sceleratus, S. pachygaster </em>and<em> T. flavimaculosus</em> cytochrome b gene sequence from the eastern Mediterranean coast of Turkey.</p> Servet Ahmet Doğdu Cemal Turan Copyright (c) 2021 Servet Ahmet Doğdu, Cemal Turan 2021-06-30 2021-06-30 30 1 1 11 FORM FACTOR OF JAPANESE THREADFIN BREAM, ‎NEMIPTERUS JAPONICUS (BLOCH, 1791)‎ <p>Japanese threadfin bream, <em>Nemipterus japonicus</em> is a large-scale commercial fish found in the Pacific and Indian Ocean. Form factor (<em>a<sub>3.0</sub></em>) is used widely for comparison of the fish body shape between geographic locations. The present study was aimed to estimate the form factor of <em>N. Japonicus </em>from available literature based on empirical model. Assessed <em>a</em><em><sub>3.0</sub></em> ranged from 0.0035 to 0.0270. The median (0.0143) and 95% confidence limit (0.0130-0.0168) indicated that <em>N. Japonicas </em>poses the typical torpedo body shape ‘fusiform’. Findings on the form factor of <em>N. japonicus</em> will be effective for perceiving further body shape alteration between geographic distributions.</p> Md. Ashekur Rahman‎ Jun Ohtomi Copyright (c) 2021 Md. Ashekur Rahman, Jun Ohtomi 2021-06-30 2021-06-30 30 1 13 19 INVESTIGATION OF HAEMOGREGARINA IN SAWROW FISH (TRACHURUS MEDITERRANEUS) IN ZLITEN COASTAL AREA, LIBYA <p>This study was conducted to estimate the prevalence, mean abundance, and mean intensity of Haemogregarina infection on Sawrow fish (<em>Trachurus</em><em> mediterraneus</em>) from Zliten coast, Libya. A total of 12 specimens of Sawrow fish species were collected randomly, the length (19.23 ± 0.72cm) and the weight (110.25 ± 7.88 g). The fish were transported immediately alive to the laboratory in the Department of Fish Biology and Fish Culture, College of Marine Resources, Asmarya University, where they were maintained alive in well aerated glass aquaria (1x2x4 m). The gills, fins, and skin were examined for ectoparasitic protozoa using a light microscope. The results showed positive effect of haemogregarina in the Sawrow. Blood recorded the highest prevalence and abundance among all the other organs in Sawrow fish followed by kideny, liver and spleen respectively. The results provide a significant difference at (p&lt;0.01), and the results were discussed with other studies in the haemogregarinidae.</p> SAMIA H. AHMED RAMZY A. YOUSIF RADWAN ELDEHIDYA SALIM ELAAKARY Copyright (c) 2021 SAMIA H. AHMED, RAMZY A. YOUSIF, RADWAN ELDEHIDYA, SALIM ELAAKARY 2021-06-30 2021-06-30 30 1 21 29 GROWTH AND DISPERSAL OF RAZOR CLAM SOLEN ‎DACTYLUS IN THE MUDFLATS OF INDUS DELTA, SINDH ‎COAST (NORTHERN ARABIAN SEA)‎ <p>The Razor clam <em>Solen dactylus </em>is being harvested for the last 10 years from mudflats in creeks of district Thatta. The results of water and soil quality samples indicate the suitability and support for growth, dispersal, production and reproduction of <em>Solen dactylus </em>occurring in Indus delta eco-region. Water quality parameters of creeks indicated the ranges of temperature of water and air 11 to 30 ℃ and 12 to 42℃, pH of water between 8.2 to 8.9, alkalinity of water 267 to 480 mg/l, hardness of water 620 to 1150 mg/l, salinity of water from 22 to 33 ppt. The soil samples of mudflats indicated silt clay 15 to 30%, sandy clay 20 to 40% and fine sand 30 to 40%. Spring, summer and early winter seasons are suitable timing for harvesting razor clam. However, winter cold and rainy seasons are not suitable for razor clam fishing. In winter, the animals become inactive and remain in deep barrows and do not come to the surface. In period of rainfall the razor clam holes were filled with fine silt thus large number of razor clam were affected and even deaths may have been caused if mudflats were exposed at the time of rain.</p> <p>The recorded mature size of razor clam ranged between length of 6 to 3.5 cm and weight 12 to 40 grams. A trained person dig-out 1.5 to 3 kg of razor clam in 1<sup>2</sup>meter square in 20-40 minutes. Thus a person can exploit 10-20 kg of razor clam in a period of 3- 4 hours, hence 15 - 20 kg of live razor clam can be harvested in a day or night by a person when mudflat become exposed after tidal action. Coastal communities inhabiting creek areas are engaged in its harvesting using traditional techniques of using salt and probing with thin sticks and hauling razor clams from burrow during low tides when mudflats become exposed. It is concluded that Razor clam is an ecologically important group of marine organism, lives in mudflats and creek systems. Although the razor clams are not locally consumed by native people of Pakistan but it is a fishery having export value which foreign exchange earned by exporting it to South East Asian countries.</p> PIRZADO A. A MUKHTIAR A. MAHAR Copyright (c) 2021 PIRZADO A.A. , M.A. MAHAR 2021-06-30 2021-06-30 30 1 31 41 BENTHIC ASSEMBLAGES FOR ECOLOGICAL EVALUATION ‎OF LAKE MANZALA, MEDITERRANEAN SEA, EGYPT <p style="margin: 0in; text-align: justify;">Lake Manzalah one of the northern Nile Delta in Egypt is the largest lake, which lies between the lakes Borollus and Bardaweel and connects to the Mediterranean Sea. It has an area of current 250 thousand acres. It contains many islands particularly along the south-western region forming of semi-enclosed basins and it is characterized by dense submerged hydrophytes as <em>Pomatogeton pectinals; Ceratophyllum</em> <em>demersum</em> and floating hyacinth <em>Eichhornia</em> <em>crassipes.</em> Seven major drains are loading directly in the south to the west. Lake Manzalah-bottomed shallow (0.5-1m), brackish water (3-18‰ and is suffering from the phenomenon of high nutrition (eutrophication) due to increased rates of nutrients and organic matter. So some sources of wastes discharges such as sewage and industrial waste and agricultural activity pour directly into the lake, especially the southern region (Bahr El Baqar Drain). The study aims to study the distribution of benthic organisms in the lake and knowledge of the relationship between the types and aggregates benthic food ecosystem as the important food sources' for some aquatic organisms, especially economic fish and crustaceans in study stations. Bottom sediment samples were collected from 11 sites by grab sampler covering different environments lake and from 4 drains consists mostly of organic materials (sludge) is made up of waste sewage, industrial, agricultural waste plants, and calcareous shells empty. Results indicate for examining configuration qualitative macro benthic recording the 16 species of aquatic plants and invertebrates where empty calcareous shells were more frequent. The abundance of macrobenthic organisms at different sampling sites along Lake Manzala can be ranked as follows: Ostracoda (45.4%, 1010 ind/m<sup>2</sup>) &gt; submerged plants (12.9%, 287 tufts/m<sup>2</sup>) &gt; Amphipoda (9.2%, 207 ind ∕m<sup>2</sup>) &gt; Polychaetes (7%, 110 ind ∕m<sup>2</sup>) Bivalves (5.9%, 132 ind ∕m<sup>2</sup>). The biomass of benthic assemblages at different sampling sites can also be ranked as follows: at ST5 (18.1%, 4433 ind ∕m<sup>2</sup>) &gt; St6 (11.3%, 2772 ind ∕m<sup>2</sup>) &gt; ST8 (9.8%, 2405 ind ∕m<sup>2</sup>) &gt; ST3 (9.2%, 2247) &gt; ST7 (8.7%, 2122 ind ∕m<sup>2</sup>). The biomass of benthic assemblages at different sampling sites can also be ranked as follows: echinoderms (52%) &gt; molluscs (27%) &gt; crustaceans (16%) &gt; polychaetes (2%) &gt; other groups (3%). Due to the increase of pollutants extensively loaded into the drains are the possible factors having affecting the constituents’ structures of benthos. Sites of sampling study were evenly spread (J’ &gt; 0.8) only at sites 6 and 8, moderate diversity (H’ &gt; 1.00) was at most sites and show lower value at sites 3 and 11 and 0 at site 1. The abiotic environmental effects in the lake are general to those generally observed in other areas influenced by organic wastes, namely, changes in the physic-chemical properties of the sediments and low oxygen concentrations in the bottom water due to the decomposition of organic materials.</p> MOHAMED MOHAMED EL KOMI Copyright (c) 2021 MOHAMED MOHAMED EL KOMI 2021-06-30 2021-06-30 30 1 43 75