scholarly journals Novel Comprehensive Molecular and Ecological Study Introducing Coastal Mud Shrimp (Solenocera Crassicornis) Recorded at the Gulf of Suez, Egypt

2020 ◽  
Vol 9 (1) ◽  
pp. 9
Author(s):  
Eman M. Abbas ◽  
Fawzia S. Ali ◽  
Mohammed G. Desouky ◽  
Mohamed Ashour ◽  
Ahmed El-Shafei ◽  
...  

Solenocera crassicornis is a commercially important shrimp of the Solenoceridae family. The current study investigated the morphology, molecular identification, phylogenetic relationships, and population dynamics of S. crassicornis in Egypt. Samples were collected monthly (total, 1722; male = 40.19%, wet weight, 0.89–10.77 g; female = 59.81%, wet weight, 1.55–19.24 g) from Al-Attaka commercial catch in the Gulf of Suez in the Red Sea. Two barcode markers, 18S rRNA and cytochrome c oxidase subunit I (COI), were used for molecular identification. COI partial sequences were used to construct the phylogenetic relationships among different species of genus Solenocera and to infer the origin of the studied Solenocera crassicornis. The applied molecular markers successfully identified the studied species to the species level. The genetic distances among S. crassicornis sequences from different countries revealed the Indo-West Pacific origin of S. crassicornis. The relationship between total length (TL) and total weight (TW) was TW = 0.035TL2.275 and r2 = 0.805 for males and TW = 0.007TL3.036 and r2 = 0.883 for females, indicating that females were heavier than males. Despite its social and economic relevance in the area, information on the hatching, larval rearing, and farming of S. crassicornis is scarce and requires future studies under Egyptian conditions.

Author(s):  
D. Sahoo ◽  
S. Panda ◽  
B.C. Guru

Portunus pelagicus a commercially important crab species found in Chilika lagoon constitutes about 20% of the total crab production. The carapace width (CW) ranges from 4.5–10.5 cm in both the sexes during the study period. The maximum abundance of male was at 6.6 to 7.5 cm CW whereas the females predominate from 6.6 to 9.5 cm CW. The relationship between carapace length (CL) and CW is linear in both sexes which indicates isometric growth. However, the relationship between CL, CW with total body weight (TW) is exponential. The food habit from gut content analysis shows that the species is highly carnivorous and the main food items include prawn carapace and appendages (27.58%), molluscan remaining (21.55%), fish bone (7.75%), seagrass (1.72%), unidentified materials (4.31%) and the mixed food (37.06%). The feeding index was found highest (80.95%) in February whereas it is lowest (60.9%) in June. The mature females are observed from May to July with a peak in July in the lagoon. The highest gonadosomatic index is found in July with an average CW of 10.5 cm. No berried females are found in the study period, which indicates that it did not spawn inside the lagoon and migrates to the sea during the rainy season.


1985 ◽  
Vol 42 (5) ◽  
pp. 989-998 ◽  
Author(s):  
G. H. Winters ◽  
J. P. Wheeler

The relationship between commercial catch-rates and population density upon which many stock assessment models depend assumes that stock area (A) is constant and independent of population abundance. Starting from a theoretical demonstration that the catchability coefficient (q) is inversely proportional to A, we establish the empirical basis of this relationship through comparisons of q and A of various Northwest Atlantic herring (Clupea harengus harengus) stocks and, in more detail, for Fortune Bay herring. For these stocks the relationship was of the form q = cA−b. For Atlantic herring stocks, levels of b were in excess of 0.80. In Fortune Bay herring, reductions in abundance were accompanied by proportional reductions in A, which in turn was inversely correlated with changes in q. School size, measured as catch per set, also declined as population levels declined but the change was not proportional. Published findings indicate that pelagic stocks in particular, and fish stocks in general, exhibit a common response of reductions in A with interactive increases in the q during periods of rapid population decline. We conclude that the conventional assumption of a constant stock area is usually violated due to the systematic interaction between A and population abundance which is reflected in an inverse relationship between stock abundance and q. Calibration of sequential population models should therefore be restricted to research vessel data collected in a standard manner and covering the distributional area of the stock.


2007 ◽  
Vol 76 (1) ◽  
pp. 35-54 ◽  
Author(s):  
Francesca Benzoni ◽  
Fabrizio Stefani ◽  
Jaroslaw Stolarski ◽  
Michel Pichon ◽  
Guillaume Mitta ◽  
...  

The phylogenetic relationships of the scleractinian genus Psammocora with the other genera traditionally included in the family Siderastreidae and some Fungiidae are assessed based on combined skeletal and molecular data. P. explanulata differs from the other examined congeneric species (P. contigua, P. digitata, P. nierstraszi , P. profundacella, P. superficialis, and P. stellata) in possessing interstomatous septa between adult corallites, costae, and in having continuous buttress-like structures joining septal faces (i.e., fulturae) which typically occur in fungiids. These characters are shared with Coscinaraea wellsi but not with the remainder of the examined siderastreids (the congeneric C. columna, and Anomastraea irregularis, Horastrea indica, Pseudosiderastrea tayamai, Siderastrea savignyana) whose septa are interconnected by typical synapticulae. Most of the examined species form septa with distinct transverse groups of centers of calcification, a biomineralization pattern typical of the Robusta clade. The observations on skeletal structures corroborate the results of the ITS2 and 5.8S molecular phylogeny. C. wellsi and P. explanulata are phylogenetically very close to each other and show closer genetic affinity with the examined Fungiidae (Halomitra pileus, Herpolitha limax, Fungia paumotensis, and Podabacia crustacea) than with the other species in the genera Psammocora and Coscinaraea, or with any other siderastreid. Our results show that neither Psammocora nor Coscinaraea are monophyletic genera. The high genetic distances between the species of Siderastreidae, especially between Pseudosiderastrea tayamai and Siderastrea savignyana on one side and the other genera on the other, suggest a deep divergence in the phylogenetic structure of the family.


1998 ◽  
Vol 20 (1) ◽  
pp. 25
Author(s):  
M. Long ◽  
R.J. Reid ◽  
C.M. Kemper

Twenty Tursiops truncatus and 20 Delphinus delphis from South Australia were analysed for cadmium levels, as were some fish and squid species which form part of their diet. In the dolphins, cadmium was accumulated mainly in the kidneys (range 0-38 μg/g), with levels in many individuals exceeding 20 μg/g (wet weight). On average, levels in kidney were three-fold higher than in liver and 26-fold higher than in muscle. Cadmium concentrations related to dolphin body length, but the relationship with tooth development class was less clear. 80% of the prey fish species analysed from Spencer Gulf exceeded NH & MRC health recommendations of 0.2 μg/g (wet weight) for human consumption. Sepioteuthis australis from upper Spencer Gulf contained significantly higher cadmium levels than Ceduna samples (0.21 ± 0.01 μg/g versus 0.13 ± 0.01 μg/g, p<0.001) (wet weight). On histological examination, 32% of adult dolphin kidneys showed pathological changes, proteinuria being the most common abnormality. High levels of cadmium were found in dolphins from widely spaced locations in South Australia.


2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Chin How Lee ◽  
Jack S. H. Oon ◽  
Kun Cheng Lee ◽  
Maurice H. T. Ling

Escherichia coli is commonly found in intestine of human, and any changes in their adaptation or evolution may affect the human body. The relationship between E. coli and food additives is less studied as compared to antibiotics. E. coli within our human gut are consistently interacting with the food additives; thus, it is important to investigate this relationship. In this paper, we observed the evolution of E. coli cultured in different concentration of food additives (sodium chloride, benzoic acid, and monosodium glutamate), singly or in combination, over 70 passages. Adaptability over time was estimated by generation time and cell density at stationary phase. Polymerase chain reaction (PCR)/restriction fragments length polymorphism (RFLP) using 3 primers and restriction endonucleases, each was used to characterize adaptation/evolution at genomic level. The amplification and digestion profiles were tabulated and analyzed by Nei-Li dissimilarity index. Our results demonstrate that E. coli in every treatment had adapted over 465 generations. The types of stress were discovered to be different even though different concentrations of same additives were used. However, RFLP shows a convergence of genetic distances, suggesting the presence of global stress response. In addition, monosodium glutamate may be a nutrient source and support acid resistance in E. coli.


1993 ◽  
Vol 71 (4) ◽  
pp. 586-591 ◽  
Author(s):  
R. E. Vaillancourt ◽  
N. F. Weeden

The cowpea (Vigna unguiculata (L.) Walp.) is an important crop of tropical Africa, Asia, and South America. However, the relationship between the cowpea and other species of subg. Vigna is relatively unknown. The objective of this study was to assess the genetic distance among species of subg. Vigna using isozymes. Twenty-four populations of the cowpea species and 39 populations from 10 other species (at least one species per section of subgenus Vigna) were sampled. Nei's genetic distance was calculated from allelic frequencies at 26 isozyme loci. UPGMA cluster analysis was performed. The range of genetic distance among species of subg. Vigna (0.41 – 2.69) was greater than previously reported in most plant genera. Three clusters of species were apparent. The first cluster included three species of sect. Vigna (V. luteola, V. oblongifolia, and V. subterranea (the Bambara groundnut)). The second cluster grouped together sections Liebrechtsia and Macrodontae. The third cluster included V. unguiculata, V. reticulata, and V. vexillata. The distances between species of this cluster were large and of similar size in all combinations (range from 0.92 to 0.95). None of the species included in this survey can be called a close relative of V. unguiculata. Key words: Vigna, cowpea, isozymes, genetic distances.


2001 ◽  
Vol 61 (1) ◽  
pp. 1-6 ◽  
Author(s):  
L. M. BINI ◽  
A. S. G COELHO ◽  
J. A. F. DINIZ-FILHO

The Energetic Equivalence Rule (EER) is a controversial issue in ecology. This rule states that the amount of energy that each species uses per unit of area is independent of its body size. Here, we perform a meta-analytical procedure to combine and compare the slopes of population density and body size relationships across independent studies of mammals and birds. We then compared a distribution of 50,000 bootstrap combined slopes with the expected slope (b = -0.75) under the EER. The combined slopes obtained for mammals and birds separately were -0.755 and -0.321, respectively. The homogeneity hypothesis (i. e. within studies the slopes differ by no more than would be expected due sampling variation) was rejected in both cases. So, EER cannot be supported since the use of an exponent of -0.75 is, in fact, an oversimplification. Significant heterogeneity of slopes within each group (mammals and birds) is an indicator of inferential problems related with variation in body size, spatial scale, the regression model adopted and phylogenetic relationships among species. So, we consider that questions regarding the estimation and validity of slopes is the next challenge of density-body size relationship studies.


Zootaxa ◽  
2016 ◽  
Vol 4196 (2) ◽  
pp. 289
Author(s):  
SERGIO TICUL ÁLVAREZ-CASTAÑEDA ◽  
CONSUELO LORENZO

Since Sylvilagus bachmani (Lagomorpha: Leporidae) from the Baja California Peninsula and S. mansuetus from San Jose Island, Mexico, display an allopatric distribution and are closely related, their taxonomy is unclear. The phylogenetic relationships among specimens of both species were evaluated using two mitochondrial genes (Cyt b, COI) and the beta-fibrinogen nuclear gene intron 7 (β-fib I7). The genetic analyses revealed that S. mansuetus was included within the S. bachmani clade as the sister-group of S. b. cerrosensis. The genetic distances among S. b. cerrosensis and mansuetus were relatively low (1.3% with Cyt b), similar to intraspecific distances observed within other species of Sylvilagus. We consider mansuetus to be a subspecies of S. bachmani, and the morphological traits previously used to differentiate the two taxa should be used to distinguish S. b. mansuetus from the other subspecies of S. bachmani. 


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