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Mikroplastik (MP) telah ditemukan di berbagai lingkungan laut khususnya pada ikan, dan informasi terkait akumulasi mikroplastik pada organ-organ ikan masih sangat terbatas. Penelitian ini bertujuan untuk membuktikan keberadaan mikroplastik pada organ insang, saluran pencernaan, dan daging ikan ekonomis penting (Hemiramphus far, Siganus virgatus, dan Lethrinus lentjan) di perairan Pulau Barranglompo, Makassar, serta mengidentifikasi karakteristik mikroplastik meliputi warna, bentuk, dan ukuran. Setiap organ diekstraksi menggunakan KOH 20% dan pengamatan karakteristik MP dilakukan secara visual menggunakan mikroskop stereo. Hasil penelitian menunjukkan bahwa mikroplastik ditemukan di insang, saluran pencernaan, dan daging dari ketiga spesies ikan. Tingkat deteksi mikroplastik pada masing-masing H. far, S. virgatus, dan L. lentjan adalah 100%, 100%, dan 82%. Karakteristik warna mikroplastik didominasi oleh biru, bentuk mikroplastik didominasi oleh line, dan kisaran ukuran mikroplastik didominasi 1–5 mm. Penelitian lebih lanjut perlu dilakukan untuk melihat akumulasi mikroplastik pada setiap organ secara eksperimental di laboratorium.

The present study provides the complete report on the embryonic and larval development of pink ear emperor, Lethrinus lentjan (Lacepede, 1802). Eggs were obtained from captive-reared broodstock of pink ear emperors from 1-year of age maintained in a 10-tonne recirculating aquaculture system (RAS). The brood fishes spawned throughout the year without hormonal induction. Fertilized eggs (692.65 ± 6.67 μm) were pelagic, transparent, non-adhesive and with a single oil globule measuring 146.63 ± 3.51 μm. Description of the different phases of embryogenesis, namely the zygote, cleavage, blastula, gastrula, segmentation of the fish is provided. Additionally, the developments during larval development period after hatching, which extends till the completion of yolk-sac absorption (pre-larvae) and the end of metamorphosis (post-larval) are also included in the present study. The embryonic development was completed within 14 h 40 min after fertilization. The newly hatched larvae had an average body length of 1.39 ± 0.08 mm, with a yolk sac measuring 787.67 ± 42.65 μm. The mouth opening was observed at 2 days post-hatch (dph). The yolk sac was completely absorbed by 2 dph, and the preflexion stage began, and it continued till 14 dph. Notochord flexion began by 15 dph and extended to 20 dph. The appearance of the typical adult colouration and scale formation started by 22 dph and by 35 dph the larvae reached the juvenile stage. The data on the embryonic and larval development will help to standardize the larval rearing techniques for the species.

Family Lethrinidae (Sho´our fishes, Shaari fishes) is one of the key families in the Red Sea and Indian Ocean fisheries. Some of its species were recorded in the International Union for Conservation of Nature (IUCN) Red List of species as endangered. In order to develop simple genetic marker that aid their rapid identification, fin clips of four lethrinid species were collected from local fish markets in Hurghada city. These species were Lethrinus lentjan, L. harak, L. microdon, and L. mahsena. DNA was extracted from these samples and subjected to polymerase chain reaction (PCR) amplification for the mitochondrial 12S ribosomal RNA (rRNA) and the nuclear 5S rRNA genes. The 12S rRNA PCR amplicons were sequenced. GenBank comparison and phylogenetic analysis for the 12S rRNA gene sequences resulted in clear identification for the sampled species. Meanwhile, a simple, 2% agarose gel electrophoresis for the 5S rDNA ran in a low voltage for 2 hours resulted in variable intraspecific patterns. These patterns appeared as 3 PCR bands of approximately 500 base pair (bp) in length for L. lentjan; 2 PCR bands at 500 and 400 bp for L. harak; single PCR band at 500 bp for L. microdon; and 3 bands at about 750, 500, and 400 bp for L. mahsena. Band separation was clear enough. 5S rDNA exhibited an accurate, interspecific, and easy-to-use genetic marker for identification of different lethrinid species covered by the current study.

Pink ear emperor, Lethrinus lentjan (Lacepede, 1802), belonging to the family Lethrinidae (oder: Perciformes) is an important food fish in India, Arabian Gulf and other South East Asian countries. The present communication gives detailed information on its captive broodstock maturation in RAS, natural spawning, larval rearing and seed production for the first time. Fertilized eggs (714.21 ± 11.91 μ) were transparent, pelagic, non-adhesive with single oil globule (146.63 ± 3.51 μ). Green water system was used for larval rearing. Size of hatchling ranged from 1355.1 μ to 1534.6 μ and mouth (110–148.2 μ) opened on 2nd dph. Larvae were reared using copepods, rotifer, artemia and micro diet. Squamation and intense pigmentation on the body began by 22 dph and by 25–30 dph larvae started moving from pelagic to benthic realm. Larvae became juvenile (length – 19.2 mm; weight – 0.096 g) after 35 dph resembling the adult fish colourations and by 46 dph, they attained an average body length of 27.83 mm and average body weight of 0.276 g. Fishes spawned throughout the year in RAS without any hormonal manipulation. Average percentage survival at seed stage was 2.85 ± 1.41.

A total of 593 samples of Lethrinus lentjan (Lacepede, 1802) were collected from the Red Sea, Jeddah, Saudi Arabia, to study their productive biology and spawning season of the local population. Sampling was carried out on a monthly basis for a period of one year. The monthly sex ratios indicated that females were dominant throughout the study period, with an overall male:female sex ratio of 1:7.98, although males were larger than females. The highest monthly performance maturation index (PMI), as well as the male and female gonadosomatic index (GSI) and ovarian maturation rate (OMR) were observed in February and March. Histological examination of the gonads confirmed the process of sexual transformation in this fish species, wherein individuals mature first as female, and then change sex to male (protogynous hermaphroditism). Histological sections also showed that the sexual maturation of males of L. lenjtan comprised three main stages, while the sexual development of females could be classified into four main stages. Extended spawning in the form of batches released during different months throughout the year were recorded for this fish species, with the main spawning season in February and March, and an additional, shorter spawning season in September.

The current parasitological study was carried out to investigate helminth parasites infecting the Red spot emperor Lethrinus lentjan inhabiting Hurghada City at the Gulf of Suez, Red Sea, Egypt. Third-stage larvae of nematode parasite was isolated from the intestine as well as body cavity of the examined fish. Light and scanning electron microscopy revealed that this parasite belonged to Anisakidae family within the genus Pseudoterranova. The present species is named Pseudoterranova decipiens based on the presence of triangular mouth aperture with prominent boring teeth and soft swellings of the cuticle, long muscular esophagus, ventrally excretory pore, and narrow transverse slit of anal opening followed by a short mucron. The morphological characteristics of this species were confirmed by molecular analysis of 18S rDNA gene region of the present parasite. It demonstrated a close identity ≥89% with taxa under family Anisakidae, 85% with Raphidascarididae, and 79-84% with Toxocaridae. A preliminary genetic comparison between gene sequence of the present parasite and other oxyurid species placeed it as a putative sister taxon to other Pseudoterranova decipiens described previously. This study demonstrated that the 18S rDNA gene region of Pseudoterranova decipiens yielded a unique sequence that confirmed its taxonomic position in Anisakidae. Resumo O presente estudo parasitológico foi realizado para investigar os helmintos parasitos que infectam o peixe imperador Lethrinus lentjan, que habita a cidade de Hurghada no Golfo de Suez, Mar Vermelho, no Egito. Larvas de terceiro estágio de parasitos nematoides foram isoladas do intestino e da cavidade do corpo do peixe examinado. Microscopia eletrônica de luz e de varredura revelou que este parasita pertence à família Anisakidae dentro do gênero Pseudoterranova. A espécie atual é denominada Pseudoterranova decipiens baseada na presença de abertura triangular da boca com dentes proeminentes chatos e inchaços moles da cutícula, esôfago muscular longo, poro ventralmente excretor e fenda transversal estreita da abertura anal seguida por um mucron curto. As características morfológicas desta espécie foram confirmadas pela análise molecular da região do gene 18S rDNA do presente parasito. Demonstrou uma identidade próxima ≥89% com taxa sob família Anisakidae, 85% com Raphidascarididae, e 79-84% com Toxocaridae. Uma comparação genética preliminar entre a sequência genética do presente parasito e outras espécies de oxiurídeos coloca-o como um taxon irmão putativo para outros Pseudoterranova descritos anteriormente. Este estudo demonstra que a região do gene 18S rDNA de Pseudoterranova decipiens produz uma sequência única que confirma sua posição taxonômica em Anisakidae.

The present work aims to molecularly characterize some popular Saudi fish species. Seven popular Saudi fish species namely, Morgan (Nemipteru sjaponicus), Mousa (Solea solea), Hamor (Greasy grouper), Shour (Lethrinus lentjan), Dennis (Caranxsex fasciatus), Harid (Scarus arabicus) and Black surgeon (Acanthurus gahhm) were characterized using six RAPD and three ISSR as well as Rep-PCR markers. These markers produced 187 distinct bands 89.4% were considered as polymorphic bands and 10.6% were considered as monomorphic bands. The RAPD OPA-06 primer revealed 100% polymorphism for 19 produced bands where band width ranged from 190 to 2100 bp. Likewise Rep- PCR ERIC1R primer exhibited 100% polymorphism for 18 bands produced bands where band width ranged from 50 to 1400bp. Data of the three types of genetic markers were combined for phylogenetic analysis. The resulted dendergram produced two large linages with around 59% genetic similarity. One linage only included Morgan (Nemipteru sjaponicus), and the other linage comprised the other six species. This result suggested that this six species were descended from Morgan fish. The second linage comprised two clades; the first clade contained four species (Mousa, Hamor, Shour, and Dennis), where the next clade included only Harid and Black surgeon. Generally genetic distance among native fishes was relatively low. The smallest genetic distance (0.512) was estimated between Shour fish and Black surgeon fish. To the best of our knowledge this work is breaking new ground in two directions, first, molecular characterization of Saudi fish, second employment Rep- PCR genetic marker for molecular characterization of fish species. This work could be considered as preliminary work towards an establishment of Saudi genetic conservation program.Int J Appl Sci Biotechnol, Vol 3(2): 359-366 DOI: http://dx.doi.org/10.3126/ijasbt.v3i2.12747

Lethrinus lentjan, Lethrinus nebulosus, Lethrinus borbonicus, Lethrinus microdon, Sphyraena jello, Scomberomorus commerson, Euthynnus affinis, Carangoides chrysophrys and Caranx sexfasciatus are important fish of artisanal fishery of Mocha. In this area, no data is available on the biology and feeding ecology of these species. From May 2014 to June 2015, fish specimens (789) were sampled from the main fishing-landing site. Total length and total weight were measured and stomach contents were analyzed to evaluate the trophic interactions that exist between these species. Fish prey dominated in diets of all species except of L. nebulosus and L. lentjan, which mainly fed on mollusks. Based on diet similarity, four fish groups were identified: one includes L. microdon, C. chrysophrys, E. affinis and L. borbonicus, the other includes C. sexfasciatus, S. jello and S. commerson. Individually, L. lentjan and L. nebulosus form two separate groups. High dietary overlap was obtained among most species, associated with the dominance of small fish pelagic prey, perhaps because its abundance in the area, this implies a generalized and opportunistic utilization of resources.

Life-history characteristics of six tropical Lethrinus species sampled from the Great Barrier Reef World Heritage Area were compared. Two species groups were identified based on fork length (LF): large species with maximum LF > 640 mm (longface emperor Lethrinus olivaceus, yellowlip emperor Lethrinus xanthochilus and spangled emperor Lethrinus nebulosus) and small species with maximum LF < 480 mm (Pacific yellowtail emperor Lethrinus atkinsoni, pink ear emperor Lethrinus lentjan and ornate emperor Lethrinus ornatus). Lifespan was not correlated with LF. Early growth for all species was rapid and similar during the first few years of life, but coefficients of the von Bertalanffy growth function varied considerably among species. Growth also differed between sexes for L. atkinsoni. Reproductive characteristics varied among species, with peak periods of spawning occurring in November to December for L. atkinsoni, July to August for L. nebulous, September to October for L. olivaceus and a protracted season for L. lentjan, although fewer samples were available for the last two species. Sex-specific LF and age distributions and gonad histology of L. lentjan were suggestive of a functional protogynous reproductive pattern, as observed in other lethrinids. Gonad histology indicated non-functional protogynous hermaphroditism for L. atkinsoni and L. nebulosus. The diversity of life histories among these closely related species emphasizes the difficulty in devising single management strategies appropriate for multi-species fisheries and illustrates the importance of understanding species-specific life histories to infer responses to exploitation.

Adult worms of Rhadinorhynchus dorsoventrospinosus (Acanthocephala: Rhadinor-hynchidae) were collected from the small intestine of the red spot emperor Lethrinus lentjan (family Lethrinidae) from locations along the Red Sea at Jeddah City, Saudi Arabia. Twenty three out of 70 fish specimens (32.9%) were found to be naturally infected. The parasite was described using photo research Zeiss microscopy and a scanning electron microscope (SEM). Light microscopic studies revealed that the adult worm possessed a proboscis which was long, cylindrical with a uniform width measured 0.44 +/- 0.02 (0.38-0.46) mm in length and 0.1 +/- 10.02 (0.09-0.15) mm in width. Proboscis hooks observed by scanning electron microscopy were large, uniform in size (14-16 rows of 26 hooks each) with a row of longer hooks at the base. Comparison between the present described species and four species of the same genus was done, it was observed that there was only one comparable species, R dorsoventrospinosus resembled the present parasite in the general morphology and differed from others, so the present studied species is classified as R. dorsoventrospinosus with new host and locality records.

Effective management is necessary if small-scale fisheries, such as those found in mixed habitats including seagrass and coral reefs, are to continue providing food for many of the poorest communities of the world. Gear-based management, although under represented and under studied, has the potential to be adaptive, address multiple objectives, and be crafted to the socio-economic setting. Management effectiveness in seagrass and coral reef fisheries has generally been evaluated at the scale of the fish community. However, community level indicators can mask species-specific declines that provide significant portions of the fisheries yields and income. Using a unique dataset, containing ten years of species level length frequency catch data from a multi-gear, multi-species seagrass and coral reef fishery in Kenya, we evaluate species specific fishery statuses, compare gear use to gear regulations and estimate the potential needs for further gear restrictions. Despite the high diversity of the fishery, fifteen species represented over 90% of the catch, and only three species represented 60% of the catch. The three most abundant species in the catch, Lethrinus lentjan (Lacepede), Siganus sutor (Valenciennes) and Leptoscarus vaigiensis (Quoy & Gaimard) all showed evidence of growth overfishing. Lethrinus lentjan, with an exploitation rate of 0.82, also shows evidence of recruitment overfishing. Current legal but weakly enforced gear restrictions are capable of protecting a significant portion of the catch up to maturity but optimization of yield will require that the current mesh size be increased from 6.3 to 8.8 and 9.2 cm to increase yields of L. lentjan and S. sutor, respectively. Given the difficulties of enforcing mesh size, we recommend that the economic benefits of these larger mesh sizes be communicated and enforced through co-management. This abstract is also available in Kiswahili (Abstract S1).

Pseudopycnadena tendu sp. nov. is described from the balistid Pseudobalistes fuscus from the waters off New Caledonia. It differs from the only other member of the genus P. fischthali Saad-Fares et Maillard, 1986, in its broad cirrus-sac, with the wide field of large gland-cells, its less nearly circular body shape, its dorsal excretory pore, its shorter post-testicular region, its relatively larger ventral sucker and its smaller eggs. The genus is re-defined to take these distinctions into account. Other opecoelid species reported from New Caledonia are Allopodocotyle epinepheli (Yamaguti, 1942) from Epinephelus cyanopodus, E. fasciatus and E. merra, Cainocreadium epinepheli (Yamaguti, 1934) from E. coeruleopunctatus, E. fasciatus and Variola louti, Hamacreadium mutabile (Linton, 1910) from Lutjanus fulviflamma and L. kasmira, Helicometra epinepheli Yamaguti, 1934 from E. fasciatus and E. merra, Orthodena tropica Durio et Manter, 1968 from Lethrinus lentjan, Pacificreadium serrani (Nagaty et Abdel-Aal, 1962) from Plectropomus leopardus and Pseudoplagioporus interruptus Durio et Manter, 1968 from Lethrinus rubrioperculatus.