Priacanthus Tayenus Research Articles

Food Preference of Purple‐Spotted Bigeye (Priacanthus tayenus Richardson 1846) in Northern Coast of Java, Indonesia

ABSTRACTDiet is one of the essential information used in the management of fisheries resource. The objective of this study was to assess the dietary preferences, index of preponderance, trophic level, food niche breadth, and food overlap of purple‐spotted bigeye (Priacanthus tayenus) caught from the northern coast of Java, Indonesia. A total of 407 fish samples were collected from July to October 2023. Each fish sample was measured for total length and body weight. Fish were then dissected to determine sex, gut length, gut volume, and diet composition. Data analysis included relative gut length, diet composition, frequency of occurrence, trophic level, index of preponderance, food niche breadth, and food overlap. The result showed that the purple‐spotted bigeye is a carnivorous fish (trophic level ranges from 3.88 to 4.18), whose main food is fish and shrimp. Based on the niche breadth value, purple‐spotted bigeye from East Java were more diverse in finding food (niche breadth = 0.26) than from West Java (niche breadth = 0.06) and Central Java (niche breadth = 0.09). The purple‐spotted bigeye species from West Java and Central Java exhibited a high level of competition in their search for food, as indicated by a food overlap value of 0.998.

Taxonomic Status of Diplectanum robustitubum Wu & Li, 2003 (Monogenoidea: Diplectanidae) from the Purple-Spotted Bigeye Priacanthus tayenus (Priacanthidae) and the Description of Platycephalotrema parile n. sp. (Monogenoidea: Dactylogyridae) from the Bartail Flathead Platycephalus indicus (Platycephalidae), in the Arabian Gulf

Purple-spotted bigeyes Priacanthus tayenus Richardson (Priacanthidae) and bartail flathead Platycephalus indicus (Linnaeus) (Platycephalidae) were collected from the Arabian Gulf and examined for species of Monogenoidea (Polyonchoinea) from February to December 2020. Diplectanum robustitubum Wu & Li, 2003 and an undescribed species of Platycephalotrema Kritsky & Nitta, 2019 were recovered from the gill lamellae of these hosts, respectively. Diplectanum robustitubum from Iraq was redescribed and transferred to Oliveriplectanum Domingues & Boeger, 2008 (Diplectanidae) as Oliveriplectanum robustitubum (Wu & Li, 2003) n. comb. Platycephalotrema parile n. sp. (Dactylogyridae) from Iraq and Kuwait was described and differentiated from the similar species, Haliotrema indicum Tripathi, 1959, Platycephalotrema ogawai Kritsky & Nitta, 2019, and Platycephalotrema platycephali (Yin & Sproston, 1948) Kritsky & Nitta, 2019, based primarily on the comparative morphologies of the vaginal sclerites. Haliotrema indicum was transferred to Platycephalotrema as Platycephalotrema indicum (Tripathi, 1959) n. comb. and Haliotrema swatowense Yao, Wang, Xia, & Chen, 1998 was considered a junior subjective synonym of P. indicum. The finding of O. robustitubum in the Arabian Gulf represents a new geographic record for the species.BackgroundThe present paper represents the third installment concerning the monogenoids collected during surveys to explore their diversity on the marine and freshwater fishes of Iraq. Previous installments on the monogenoids emanating from the surveys included the dactylogyrid and gyrodactylid species parasitizing mugilid fishes.PurposeThe purpose of this paper is to further document the diversity of monogenoids infecting the fishes of Iraq.MethodsMarine fishes were necropsied for parasites, and standard procedures for collecting, mounting, drawing, and measuring of monogenoids were employed.ResultsOliveriplectanum robustitubum n. comb. (Diplectanidae) and Platycephalotrema parile n. sp. (Dactylogyridae) were collected. The occurrence of O. robustitubum in the Arabian Gulf represented a new locality record for the species.ConclusionThe recorded presence of O. robustitubum and P. parile n. sp. suggests that the diversity of monogenoids in Iraq is under estimated in the literature.

The Growth Pattern and Condition Factors of Swanggi (Pracanthus tayenus Richardson, 1846) Landed at Coastal Fishing Port of Lempasing

Lempasing Coastal Fishery Port is one of the fishing ports in Lampung Province with one of the catches is Swanggi (Priacanthus tayenus) or local people call it king fish gantang. The purpose of this study was to determine the growth pattern and condition factors of Swanggi (Priacanthus tayenus) landed at the Lempasing Coastal Fishery Port as an effort to manage sustainable fishery resources. This research was conducted in May-August 2023. The method used in this research is the survey method. Sampling was done 8 times with an intensity of 2 weeks. Swanggi samples used are the result of fishermen's catch at PPP Lempasing. The results showed that male and female Swanggi had a negative allometric growth pattern. The condition factor value of male Swanggi in May-August 2023 is 1.0437; 0.9414; 1.01; 1.0057, respectively, while the female Swanggi obtained the average condition factor value is 1.4502; 0.9937; 0.9937; 1.0057.

Effect of different acids during collagen extraction the bone and fins from purple-spotted bigeye (Priacanthus tayenus Richardson, 1846) and their physicochemical properties

This study was carried out to determine the effectiveness of different acids (acetic, lactic and citric)-on the extraction of collagen from the bone and fins of purple-spotted bigeye (Priacanthus tayenus Richardson, 1846) particularly on the yield and physicochemical properties. The physicochemical properties were characterized by electrophoretic pattern, X-ray diffraction, FT-IR, colour and pH. The citric acid-extracted collagen (CAC) has a higher percentage of yield (1.93±0.57), followed by lactic acid-extracted collagen (LAC) (1.43±0.42) and acetic acid-extracted collagen (AAC) (0.83±0.18) although those collagens did not differ significantly (p>0.05), and those acid solubilized collagens (ASC) contained about 96.82 - 96.89 mg/g of hydroxyproline. The ASCs obtained showed similar electrophoretic patterns due to the presence of identical α chains (α1 and α2) and classified as type I collagen. UV absorption spectrum in all ASCs was approximately around 231.0 - 231.5 nm. For diffraction angle analysis, first diffraction was detected at 7.23 - 7.41° and second diffraction was at 19.41 - 20.29° in all ASCs. Major absorption peaks of FT-IR spectrum, viz. amide A, amide B and amide I-III were present in the collagens with different wavenumbers. The results indicated that the physicochemical properties of ASCs extracted in the present study were comparable with collagens reported from other fish species. The findings suggested that ASCs from purple-spotted bigeye bones and fins could serve as alternative source of collagen in functional food, pharmaceutics and tissue engineering production, particularly found in acetic acidextracted collagen because of its properties.

First report of Kudoa species (Myxozoa, Multivalvulida) infection in purple-spotted Bigeye (Priacanthus tayenus) from the Saudi Arabian Gulf.

The purple-spotted bigeye, Priacanthus tayenus, is a marine benthic fish native to the Indian and Pacific Oceans, including the Arabian Gulf in Saudi Arabia. This study identified a myxozoan parasite infecting wild P. tayenus from the Saudi Arabian Gulf. These parasites produced spherical to ovoid-shaped, white plasmodia enclosed within pseudocysts in the fish musculature. The annual infection rate was 5.1%, with the highest prevalence in summer (7.6%), followed by spring (6%), and autumn (2.5%), while no infections were observed in winter. The number of plasmodia per fish ranged from 100 to 150 (135.1 ± 16.2). Their dimensions were 4-4.7 mm (4.3 ± 0.3 mm) in length and 4.5-7 mm (6 ± 1.1 mm) in width. Milky-colored exudates within the plasmodia contained mature spores measuring 8-9 μm (8.6 ± 0.4 μm) x 6-7.5 μm (6.9 ± 0.5 μm). The polar capsules of the spores exhibited dimensions of 2-5 μm (3.5 ± 0.5 μm) x 2.5-4.5 μm (3 ± 0.45 μm). Both morphological and genetic analyses confirmed these plasmodia as a novel Kudoa species. Histopathological examination revealed atrophy in the surrounding muscles without an inflammatory response. This study documents the first occurrence of a novel Kudoa sp. in P. tayenus at the Jubail landing site in Saudi Arabia, emphasizing the need for further surveillance and investigations to elucidate its pathogenesis and implications for wild fish stocks.

Occurrence of Hysterothylacium Species (Nematoda: Raphidascarididae) from Some Marine Fishes from Iraqi Waters

Parasitological investigation of 22 species of marine fishes in territorial Iraqi waters, during the period from October 2019 till September 2020, revealed recording of six different species of Hysterothylacium Ward & Magath, 1917 in different developmental stages. These nematodes including two species in adult stage of Hysterothylacium viz, H. reliquens (Norris & Overstreet, 1975) and Hysterothylacium sp. (females only), two species of fourth larval stages (Hysterothylacium sp. type BH and Hysterothylacium sp. type BI) and two species of third larval stages (Hysterothylacium sp. type BA and Hysterothylacium sp. type BC). Identification of Hysterothylacium sp. was based on female only isolated from Blackfin stonefish Pseudosynanceia melanostigma Day, 1875; Hysterothylacium sp. type BH 4th larval stage isolated from Arabian backspot threadfin Polydactylus mullani (Hora, 1926) and Hysterothylacium sp. type BI 4th larval stage from purple-spotted bigeye Priacanthus tayenus Richardson, 1846; all these parasitic nematodes recorded for the first time in the Arabian Gulf. In addition, 14 fish species are considered as new hosts for Hysterothylacium sp. type BC 3rd larval stage. Description of female Hysterothylacium sp., Hysterothylacium sp. type BH and BI both 4th larval stages are given. The interest record of inverse intestinal caecum in some specimens of 3rd larval stage of Hysterothylacium type BC in some marine fishes of the current study is given.

Functional Properties of Collagen from Purple-spotted Bigeye (Priacanthus tayenus Richardson, 1846) Bone and Fins Extracted with Different Acids

This work aimed to evaluate the functional properties of collagen derived from the bone and fins of Priacanthus tayenus (Richardson, 1846) prepared with various organic acids. The extracted collagens yielded 0.83%, 1.43%, and 1.93% of acetic acid-extracted collagen (AEC), lactic acid-extracted collagen (LEC), and citric acid-extracted collagen (CEC), respectively, although no significant differences (p > 0.05). The high solubility was detected in all extracted collagen samples under low concentrations of sodium chloride (up to 20 g/L). Acetic and lactic acid-extracted collagens showed the highest solubility at pH 3 and pH 5 for citric acid-extracted collagen. The oil absorption capacity varied from 8.57 mL/mg to 15.94 mL/mg and was significantly the highest (p < 0.05) for the AEC sample. Although the highest water absorption capacity was noted in LEC (14.39 mL/mg) compared to AEC (12.44 mL/mg) and CEC (8.30 mL/mg), it is not significantly different (p > 0.05). All the extracted samples recorded higher values of foaming ability (from 78.33% to 88.33%) and stability (from 80% to 93.33%) at pH 4. Therefore, the emulsion characteristics comprising the emulsion ability and stability indexes were carried out under acidic pH conditions, and the results showed acetic-extracted collagen had the highest values compared to lactic and citric acid-extracted collagens. Taken together, P. tayenus collagens had good functional properties comparable to other collagen sources, supporting its further use in industrial processes.

The Composition of The Catch in The Danish Seine Operating in The Java Sea

Fishing gear with a good level of environmental friendliness will be selective in fishing, by choosing the right location and using net mesh sizes that can select the fish to be caught. For this reason, this study was carried out to analyze the composition of the catch from the Pocket Drag Net. The types of fish caught in percentage are as follows: swanggi fish (Priacanthus tayenus) at 29.9%; etong fish (Abalistes stellaris) by 11.2%; mackerel (Scomberomorus commerson) by 0.14%; tiger grouper (Epinephelus fuscoguttatus) by 1.5%; yellowtail fish (Caesio teres) by 1.7%; red snapper (Lutjanus sp.) by 0.7%; Stingray (Dasiatis zugei) at 1.5%; Kurisi fish (Nemipterus japonicus) amounted to 22.2%; Ray shark (Rhynchobatus australiae) by 1.15%; Brown (Scolopsis taeniopterus) by 21.2%; and Manyung (Netuma thalassina) at 7.9%. Based on the percentage composition of the catch, Swanggi fish is the highest main catch fish with a percentage of 29.9% and the lowest main catch fish is red snapper, namely 0.7%. Meanwhile, by-catch fish such as mackerel were also caught with a percentage of 0.14%.

Two new and one newly recorded gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) parasitising marine fishes in Iraq.

Specimens of two undescribed and one known gonad-infecting species of Philometra Costa, 1845 (Nematoda: Philometridae) were collected in some marine fishes from off the southern coast of Iraq. Based on light and scanning electron microscopy, the following new species are described: Philometra tayeni n. sp. (males and nongravid females) from ovaries of the purple-spotted bigeye Priacanthus tayenus Richardson (Priacanthidae, Acanthuriformes), and Philometra nibeae n. sp. (males and gravid female) from the ovary of the blotched croaker Nibea maculata (Bloch et Schneider) (Sciaenidae, Acanthuriformes). Philometra tayeni is mainly characterised by a pair of postanal papillae and a V-shaped caudal mound in males and by their body lengths (2.42-2.99 mm), whereas P. nibeae differs from its gonad-infecting congeners parasitising scienids mainly based on the body length of males (2.29-2.49 mm) and their spicules (96-117 µm), absence of a pair of postanal papillae and shape of caudal mound consisting of two parts. Philometra piscaria Moravec & Justine, 2014 (males and nongravid females), a parasite of the orange-spotted grouper Epinephelus coioides (Hamilton) (Epinephelidae, Perciformes), is recorded from the Arabian (= Persian) Gulf for the first time; previously unknown females of this species are described.

Characterization of Acid- and Pepsin-Soluble Collagen Extracted from the Skin of Purple-Spotted Bigeye Snapper.

Fish processing waste is a prospective source of collagen and a cost-effective environmental pollutant. The skin of the purple-spotted bigeye snapper (Priacanthus tayenus) was extracted utilising various acid soluble collagens (ASC) including acetic acid (AAC), lactic acid (LAC), citric acid (CAC) and pepsin soluble collagens (PSC). In this study, PSC (6.65%) had the highest collagen yield, followed by AAC (5.79%), CAC (4.15%), and LAC (3.19%). The maximum temperatures (Tmax) denaturation of AAC, LAC, CAC, and PSC were 31.4, 31.7, 31.5, and 33.2 °C, respectively. UV-VIS absorption spectra showed all extracted collagens had a range of absorbance at 230 nm, due to the presence of glycine, proline, hydroxyproline, and triple-helical collagen. Additionally, they exhibited amide A, B, amide I, II, and III peaks. SDS–PAGE identified all extracted collagens as type I. The PSC had a significantly higher (p < 0.05) hydroxyproline content than acidic extraction 66.3 ± 1.03 (mg/g sample). Furthermore, all samples were extremely soluble in acetic conditions at pH 5, and all collagen was soluble in NaCl up to 3% (w/v). Therefore, PSC was the best treatment since it did not impact collagen triple helical and acetic acid yielded the most collagen in ASC extraction. Overall, the analysis revealed that fish skin waste might be used as an alternate source of collagen in diverse applications, particularly in food applications.

Characteristics and functional properties of gelatin and gelatin hydrolysate from bigeye snapper (Priacanthus tayenus) bone

Bigeye snapper bone, a by-product from the surimi industry, was a starting material to prepare gelatin through hot water extraction (HG) and retort extraction (RG). Yields of HG and RG were 0.35 and 0.90% (based on wet weight), respectively. It was high in protein content (72.15-75.36%). Gelatins from both methods showed significant differences in the quantity of chemical compositions (P≤0.05). The HG showed greater gel strength (384 g) and viscoelastic properties than the RG (P≤0.05). Both HG and RG were then hydrolyzed by protease (papain) with a degree of hydrolysis of 43.29% and 37.22%, respectively. The functional properties and antioxidant capacities of both gelatin hydrolysates were also investigated. The HG hydrolysate (HGH) showed higher foam expansion (1.33-14.67%), but a lower emulsifying stability index (33.5-5.33 mins) than those of RG hydrolysate (RGH) (0.67-8.00% and 76.8-1.0 min, respectively). Antioxidant capacities showed that both HGH and RGH are good sources of functional ingredients in foods.

Nutritional composition and mineral analysis of the by-products from tropical marine fish, purple-spotted bigeye (Priacanthus tayenus Richardson, 1846) and barracuda (Sphyraena obtusata Cuvier, 1829)

The aim of this study is to evaluate the nutritional composition, macro- and micro-elements from purple-spotted bigeye (Priacanthus tayenus) and barracuda (Sphyraena obtusata) by product which are extensively used for surimi. The proximate composition showed significant differences (p < 0.05) for all parameters. The moisture, protein, fat, ash and carbohydrate contents of purple-spotted bigeye sample ranged from 56.22-79.26%, 12.46-31.14%, 0.24-1.29%, 1.27-22.86% and 0.42-0.98%, respectively. Meanwhile, barracuda recorded 55.76-79.86% moisture, 18.46-27.29% protein, fat 0.05-2.55% fat, 1.22-24.36% ash and 0.41-0.88% carbohydrate contents. For macro-elements analysis, both fish species contained high concentration of calcium, especially in fins, bone and skin. For other macro-elements, all samples recorded lower than 4.5 mg/g. Although the concentration of micro-element zinc and copper were dominant in all samples examined, their levels were still below the permissible limits recommended by the Food and Agriculture Organization/World Health Organization (FAO/WHO) and the Malaysian Food Regulations (MFR). More importantly, chromium, cadmium and lead were far below the toxic levels regulated by the FAO/WHO and the MFR. Thus, the by-products used may be applied for potential food ingredients and for baseline information in the further experimentation.

Impact of lecithin incorporation on gel properties of bigeye snapper (Priacanthus tayenus) surimi

SummaryGelling characteristics of bigeye snapper (Priacanthus tayenus) surimi functionalised by lecithin at different concentrations were investigated. Lecithin at ≤1 g 100 g−1 had no impact on breaking force and deformation (P &gt; 0.05). Expressible drip tended to decrease with increasing lecithin level up to 1 g 100 g−1. Lecithin at 1–3 g 100 g−1 improved the whiteness (P &lt; 0.05). Jointed clusters were formed in the gel microstructure with 1 g 100 g−1 lecithin. Gel without and with 1 g 100 g−1 lecithin had the same texture profile and likeness scores (texture, odour and flavour) (P &gt; 0.05). Peroxide value, TBARS content and rancid odour score of gels were changed considerably during refrigerated storage (4 °C/polyethylene bag) for 15 days but lower values of all indices were noticeable in gel with lecithin. Therefore, lecithin at 1 g 100 g−1 was the optimum concentration for stabilising the texture, improving the water holding capacity, whitening the colour and retarding the lipid oxidation of bigeye snapper surimi gel.

Ultraviolet/peroxydisulfate degradation of ofloxacin in seawater: Kinetics, mechanism and toxicity of products

The ultraviolet/peroxydisulfate (UV/PDS) system was used to degrade ofloxacin (OFL) in fresh water, synthetic marine aquaculture water and synthetic seawater. The comparison of the reaction degradation rate constants proved that the order of reaction rate was the following: synthetic seawater (0.77 min−1) > synthetic marine aquaculture water (0.74 min−1) > freshwater (0.30 min−1). Bromide (Br−) and bicarbonate (HCO3−) promote the degradation of OFL, whereas chloride (Cl−) inhibits the degradation. The piperazine ring of OFL was the main reactive group, and atoms N1, C6, C7 and N2 were identified as the reaction sites. Based on the intermediate and final products, the possible degradation pathways of OFL in the three kinds of water were proposed. Additionally, during the UV/PDS treatment of synthetic marine aquaculture water containing Cl− and Br−, the oxidation products of OFL showed a slight toxicity to Chlorella pyrenoidosa (C. pyrenoidosa) and Priacanthus tayenus (P. tayenus). The maximum growth inhibition rate of the products to C. pyrenoidosa was 9.72%. The products also caused liver cells of P. tayenus to be damaged and reduced the species richness and diversity of intestinal microorganism. Nevertheless, compared with the products degraded by traditional disinfection methods using NaClO, the biological toxicities were much lower. UV/PDS can be used for seawater as a new alternative disinfection method.

Analysis of Heavy Metal Accumulation in Fish at Terengganu Coastal Area, Malaysia

Bioaccumulation of toxic metals in fish causes serious threats to human when they are consumed. Thus, the detection of toxic element concentration levels in aquatic component is important. The accumulation of some heavy metals such as Cd, Cu, Fe, Mn, Pb and Zn in fish were determined. Ten species (Selaroides leptolepis, Decapterus maraudsi, Epinephelus lanceolatus, Priacanthus tayenus, Rastrelliger, Megalaspis cordyla, Nibea soldado, Pristipomoides filamentosus, Bramidae and Siganus canaliculatus) were collected from Terengganu coastal area, Malaysia. The analysis was done using inductive coupled plasma-mass spectrometer (ICP-MS) technique. In general, the concentration levels of heavy metals in fish samples are lower than the previous study in various locations. The highest average level of heavy metal recorded in fish is Fe followed by Zn, Mn, Cu, Cd and Pb. The metal concentration found in this study was lower than the national and international recommended dietary allowance (RDA) for human consumption except Fe (52.33 × 10-2 ± 6.39 × 10-2 mg kg-1) which exceeded the limit of 0.3 mg kg-1. Long term monitoring system of metal bioaccumulation in fishes need to be done to provide useful information for the assessment of the potential health risks of metals in Malaysia.

The estimates spawning potential ratio of three dominant demersal fish species landed in Tegal, north coast of Central Java, Indonesia

Nugroho D, Patria MP, Supriatna J, Adrianto L. 2017. The estimates spawning potential ratio of three dominant demersal fish species landed in Tegal, north coast of Central Java, Indonesia. Biodiversitas 18: 844-849. Java Sea is one of the important marine waters for fisheries purpose in Indonesia. The rich diversity of marine fish has been exploited for decades. Among them, demersal fish resource was commercially targeted by coastal fishers. The sustainability of demersal fishery is a crucial concern given the substantial economic contribution and its significant dependence of small-scale fishers for their livelihoods. The fishing intensity is considerable growing and tends to become threats their habitats. Three dominant species (Priacanthus tayenus, Scolopsis taeniopterus and Upeneus sulphureus) were selected in this study. To evaluate the vulnerability of these species to their bio-exploitation level, the spawning potential ratio (SPR) approach were applied. The calculation based on estimated length of first capture (Lc) indicates that SPR those demersal species occurred at less than 20%. These values indicate that existing fishery can be categorized as nearly fully exploited. Across broad range of species, 40% SPR is generally accepted as a proxy for Maximum Sustainable Yield (MSY) for recruitment overfishing in less resilience fish population.

Functional properties of pH-shifted protein isolates from bigeye snapper (Priacanthus tayenus) head by-product

ABSTRACTThe functional properties of pH-shifted protein isolates from bigeye snapper head were evaluated. Alkaline isolate showed a superior salt-solubility and gel forming ability to acid counterpart as indicated by a regular gel structure (i.e., imaged by scanning electron microscope) with higher gel strength and lower expressible drip (p < 0.05). Acid isolate exhibited higher surface hydrophobicity (p < 0.05) and thereby improved interfacial properties. Emulsifying activity index of acid isolate was lower than commercial whey protein and egg-white (p < 0.05) but its emulsion stability was better (p < 0.05). Both protein isolates had lower foamability than commercial proteins but their foam stability was not different (p > 0.05).

Biological characteristics on three demersal fish landed in Tegal, north coast of Central Java, Indonesia

Nugroho D, Patria MP, Supriatna J, Andrianto L. 2016. Biological characteristics on three demersal fish landed in Tegal, north coast of Central Java, Indonesia. Biodiversitas 17: 679-686. Java Sea has a potential marine biodiversity that has been harvested since years. Demersal fish resources is one of the targeted species by Danish seine fisheries operated in North coast of Java. To support on developing conservation and management measures, an observation on species composition, length frequencies and maturity stages were carried out during August 2014 to July 2015. Sampling took place in landing place of Tegalsari fishing port central Java. A total 129 fish species identified, among them 91 species were targeted as edible fish. Sampling on three dominant species i.e., Purple-spotted bigeye Priacanthus tayenus (Richardson, 1846), Lattice monocle bream Scolopsis taenioptera (Cuvier, 1830) and goatfish Upeneus sulphureus (Cuvier, 1829) were measured regarding length, weight and their maturity stages. The results shows that length-weight relationship for each species were P. tayenus W = 0.0324 L 2.7321, S. taenioptera W = 0.0366 L2.7262 and U. sulphureus W = 0.038 L2.7312.Monthly average GSI of P. tayenus and S. taenioptera indicated that the highest index occurred during SE monsoon while U. sulphureus on NW monsoon. Maturity stage analysis indicated that estimated of length at first maturity (Lm) were at 12.9 cmFL (U. sulphureus), 16.8 cmFL (S. taenioptera) and 19.4 cmFL (P. tayenus). Size frequency distribution shows that most of the fish were caught at immature cohorts. The diversity or evenness indices of ichtyofauna is also described as descriptors of community structure and be complemented with information on biological characteristics of those dominant species.Keywords: Demersal fish, dominant species, biological characteristics, north coast, Java

Characterization of the complete mitochondrial genome of Priacanthus tayenus (Perciformes: Priacanthidae) with phylogenetic consideration

The complete mitochondrial genome of the Priacanthus tayenus was sequenced and analyzed in this study. The mitochondrial genome is 16,866 bp long and consists of 13 protein-coding genes, two rRNA genes, 22 tRNA genes and a control region. The gene order and the composition of P. tayenus mitochondrial genome were similar to that of most other vertebrates. The nucleotide composition of the light strand in descending order is 30.91% of G, 26. 35% of T, 25.61% of A and 17.13% of C. The NADH dehydrogenase subunit 6 (ND6) and eight tRNA genes were localized in the light strand, and all other mitochondrial genes were encoded on the heavy strand. The phylogenetic analysis by maximum-likelihood (ML) method revealed that the P. tayenus showed the closer relationship to the Sciaenops ocellatus.

PERBEDAAN JENIS UMPAN DAN WAKTU PENANGKAPAN KEPITING BAKAU (Scylla serrata) DENGAN BUBU LIPAT SKALA LABORATORIUM

Mud crabs fishing by using collapsible trap could be carried on day and night with different bait. Fishing time and bait affectivity have not been considered by fisherman. The objective to determine more effective fishing time and bait in laboratoty scale. The research was conducted in laboratory with Priacanthus tayenus , Upeneus sulphurus and cowhide as bait. Fishing time was divided into three parts, in the morning, afternoon and evening. Data was analyzed by Kruskal-Wallis. The result showed that the different bait and fishing time has significantly effect on the frequency and weight of mud crab that caught. Upeneus sulphurus is preferably bait than other bait and morning fishing time is the most effective than other time. Keyword: bait, capture time, collapsible trap, mud crab ( Scylla serrata )