International Journal of Aquatic Biology
Volume:11 Issue: 2, Apr 2023

Some members of the genus Sinanodonta (Modell, 1944) are known as successful invaders of freshwater habitats. Here we report the first record of Sinanodonta lauta (Martens, 1877) from Iran and provide morphological and molecular data on this alien population. This species was observed in the Dez River and a fish farm in Khuzestan, south of Iran. The S. lauta introduction seems to be closely related to the introduction of Asian carps from East Asia. The individuals collected from the river exhibited two COI haplotypes, probably due to several introduction events of host fish. Based on our haplotype network, the alien individuals found in Iran is closer to the native ones from South Korea (two-three substitutions) compared to other native individuals reported from Japan and Russian Far East. The presence of 10-11 years old specimens in Dez River shows that the species can survive well in the natural environment of southern Iran. Further expansion and colonization of S. lauta in south Iran or beyond it are not unexpected due to some human-mediated dispersal events as well as waterways in the region.

Bioaccumulation of Cadmium, lead, Copper, Zinc, and Iron was investigated in the liver tissues of three migratory bird species viz. Anas platyrhynchos, A. crecca, and A. acuta of both sexes in autumn and winter. Bird samples were collected from autumn 2021 to winter 2022 from Al- Hawizeh Marshes, Misan Province, Iraq. The results showed that Cd in liver tissues ranged from 0.73 to 8.174 ppm during winter and autumn, respectively in males of A. crecca. Pb ranged from 0.076 to 0.922 ppm in females and males of A. platyrhynchos during winter and autumn, respectively. Cu varied from 0.635 to 4.62 ppm in males of A. platyrhynchos during autumn and winter, respectively. Zn ranged between 0.402 ppm in males of A. acuta and 2 ppm in females A. platyrhynchos and A. crecca during autumn and winter, respectively. Fe ranged between 1.544 ppm in males of A. acuta and 15.85 ppm in females of A. platyrhynchos during autumn and winter, respectively. The concentrations of Cd, Cu, and Fe were higher than the permissible limit, whereas Zn and Pb were within permissible FAO.

The effects of temperature, food concentration, and pH conditions on the life history characteristics of the freshwater rotifer, Brachionus calyciflorus, were investigated. The culture temperature (20, 25, and 30°C) had a significant relationship with life history parameters. At lower temperatures, there was a prolongation of the mean lifespan and juvenile period. The optimal temperature for the fecundity of this species was 25°C with an average quantity of 23.67±6.99 offspring female-1 across the entire lifespan of 6.7 days. No significant difference was found between the mean lifespan at different algae densities but the maximum fecundity (25.75±6.99 offspring female-1) was obtained at an algae density of 10x106 cells.ml-1. Brachionus calyciflorus could tolerate a broad range of pH (4-10) but preferred pH from 6-10. These results are critical for potential applications of this species in ecotoxicology, biomonitoring as well as in mass culture as live food for larval rearing in aquaculture.

The leucosiid crabs are common species that can be found on soft sediments ranging in depth from the intertidal flat to the shelf and slop. The Leucosiid crab, Nursia plicata (Herbst, 1803), is reported in this study based on the collection of two specimens in April 2019 from the Iraqi Marin waters. Photographs and illustrations of the species and its external morphological traits and the first male gonapod G1 are given.

A single specimen of Favonigobius gymnauchen was captured from the Iranian coast of the Persian Gulf, north-western Indian Ocean. Species identification was performed based on sequence analysis of the mitochondrial COI barcode region. This significant record from the northern Persian Gulf, adds a new species to the gobiid fauna of the north-western Indian Ocean and represents the easternmost documentation of the species. The presence of a deep phylogeographic break between the Indian Ocean and the West Pacific groups of haplotypes suggests the potential existence of hidden taxonomic diversity, hereby highlighting the necessity of a comprehensive morphological and molecular analysis of the sharp-nosed sand gobies from the two oceans.

The toxicity of the neonicotinoid pesticide Imidacloprid was tested on Lamellidens marginalis by 96-hours LC50 test and histopathology. After acute exposure to Imidacloprid, histopathological changes were noted in the gill, mantle, and digestive gland. Exposed gills showed deformed interfilamental space, fused lamellae, disrupted chitenous rod, and vacuolated cytoplasm. In the mantle, damage was observed in the inner and outer mantle epithelium and vacuole in connective tissue. The digestive gland has ruptured the digestive tubule, and basement membrane, the lumen deteriorates, and the cytoplasm appears vacuolated. Lipid peroxidation was also observed after the exposure. These findings suggest that acute exposure to Imidacloprid caused significant histological alterations in vital organs and can affect the non-targeted freshwater bivalve Lamellidens marginalis.

In the present study, the population characteristics of Spiral Babylon, Babylonia spirata, were evaluated by sampling at four sites in the northern Oman Sea, Iran, including Pozm, Konark, Beries, Pasabandar from March 2021 to March 2022. A total of 2779 Babylonian snail specimens (1489 males, and 1290 females) were measured and about ten percent of the specimens were described. The mean length and weight of males and females were 36±5, and 32±5 mm and 14±6, 10±4 g, respectively. Growth and mortality indices for females and males including infinite length (L∞ = 68 and 76 mm), growth coefficient (K = 0.54 and 0.3 (yr-1)), natural mortality (M= 0.7 and 0.4 (yr-1)), fishing mortality (F = 2.30 and 1.79 (yr-1)), total mortality (Z = 3 and 2.19 (yr-1)) and exploitation coefficient (E = 0.77 and 0.82 (yr-1)) were estimated. Based on the LBSPR assessment model, estimated to be about 0.3, and a ratio of Pmega<0.1, Lmean/Lopt <1 and Lmean /LF=M<1 show considered undesirable. The present study showed that the Spiral Babylon stock has reached 'overfished' status.

Polychaetes are suitable indicators to evaluate the benthic ecological status and respond to natural and anthropogenic. We evaluated the ecosystem health of the mangroves of Azini and Gwadar based on benthic indices including AMBI, M-AMBI, and BENTIX using polychaete communities. The results showed that in both regions, EcoQ classifications ranged from "high" to "moderate" in BENTIX, "good" to "excellent" in AMBI, and "good" in M-AMBI. The M-AMBI was significantly correlated with sediment variables, including total organic matter (TOM), total organic carbon (TOC), and silt/clay. The result revealed a significant correlation between the biotic indices and the TOC content of sediments. According to the results, TOC can be used as a descriptor and indicator to evaluate the health of mangrove ecosystems in relation to benthic indices. In addition, it is necessary to combine several indices to assess the status of ecosystems.

The presence of antibiotics in the aquatic environment poses great concerns due to their impact on water quality, aquatic organisms, and human health. The current study aims to detect the antibiotic residues (Amoxicillin (AMO), Ciprofloxacin (CIP), and Levofloxacin (LEV)) seasonally in the muscles and liver of Nile tilapia, Oreochromis niloticus, collected from Shatt Al-Arab and to know their effect on some health aspects of fish during November 2020 to August 2021 by selecting two stations in the river. The samples were analyzed using high-performance liquid chromatography (HPLC) for measuring antibiotics. The study revealed high concentrations of antibiotics in the muscles and liver of fish, and the concentrations were higher in the second station. CIP had the highest concentration (7.4 mg/kg) in muscles in the spring, and the AMO showed the highest concentration (4.1 mg/kg) in the liver during the spring. The study also showed that the accumulation of antibiotics in the liver and muscles of fish had negative effects on the health standards of fish. The presence of antibiotic residues in fish samples in high concentrations is a source of great concern as it is a major source of human food.

The microalga Nannochloropsis oculata is marine widely used in aquaculture systems as an essential source of protein, lipid, and polyunsaturated fatty acids. Day/night pH fluctuations driven by photosynthesis and respiration create an environment that exhibits changing pH ranges. The aim of this study was to find whether physical shocks could change the complete profile of nutrients (lipid, fatty acid, carbohydrate, chlorophylls, and proteins) in N. oculata. The algae were cultivated in 32 flasks of ten-liter for biomass production for 12 days using Guillard medium (f/2). The cells were reared at 0.5 molar salinity (29 ppt), under 3500 lux light intensity with a 12L:12D photoperiod and 21ºC temperature. After 12 days, when the cell density reached its stationary phase, they were centrifuged. The pellets were then re-suspended in fresh seawater thoroughly and transferred into thirty-two containers with 10-liter volumes, including eight treatments with four replicates. The algae in treatments 3, 4, and 8 were subjected to salinity (88 ppt), starvation, and pH (11) shocks, respectively and treatments 2, 5, 6, and 7 were subjected to salinity + pH + starvation, pH + starvation, salinity + pH and salinity + starvation shocks, respectively. The biochemical composition of N. oculata demonstrated that T3 at the end of the dark period, and T1 at the end of the light period, possessed significantly higher (51.51%), and lower (24.9%) lipid content, respectively. According to the results, EPA under pH shock, linoleic acid under pH + salinity + starvation shock, and DHA and omega-3 under pH + salinity shock at the end of the dark period revealed significant differences with the control group. The saturated fatty acids showed significantly higher value in the control group during the dark period. The monounsaturated fatty acids increased significantly under pH shock at the end of the light period on day 18. Based on the results, the best treatment to obtain more lipid production in N. oculata was using six-day salinity shock and harvesting algae at the end of the dark period, and for more EPA synthesis in N. oculata, pH shock for six days and harvesting the algae at the end of dark period is recommended.