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A total number of 100 Nemipterus japonicus was collected randomly from the Western Gulf of Suez, Red Sea, Egypt from September to April 2021. After external and internal examinations, two species of parasites were found. The first species was Mothocya melanosticta isopods (both sexes) with a prevalence of 52% and attached externally to the gills and inside the buccal cavity. The second species, Hysterothylacium aduncum nematodes that was found in three types of distributions in 53 fishes. Firstly, adults were found in the gastrointestinal (GI) tract with a high prevalence of about 58%. Secondly, larval stages were found in 52 fishes with a high prevalence of about 57%. Thirdly, adults and larvae were found mixed together in 91 fishes with a high prevalence of 91% inside the GI tract of the same host. There was mixed infestations with M. melanosticta and H. aduncum with a percentage of 51% with several observed signs on the infested fishes. To determine the correct identification of detected parasites, both species were subjected to morphological and electron microscopic examination. Based on the present findings, further studies are recommended on the host-parasites relationship. [ABSTRACT FROM AUTHOR]

The third stage larvae (L3) of Anisakis typica were detected in 2 species of threadfin bream, Nemipterus hexodon and N. japonicus, from the Gulf of Thailand, and were morphologically and molecularly characterized. Total 100 threadfin breams, 50 Nemipterus hexodon and 50 N. japonicus, were examined with naked eyes after the opening of abdominal cavity with scissors. Almost all infected larvae remained alive and active even the fish were transported for 1-2 days. Anisakid larvae were exclusively distributed in the body cavity and rarely in the liver. The prevalence of A. typica L3 were 68.0% and 60.0% in N. hexodon and N. japonicus and their infection intensities were 3.5 and 4.2 per fish infected each. Morphological and morphometric analysis were performed by viewing specimens under both a light microscope and a scanning electron microscope. Interestingly, the protruded mucron of Anisakis typica under SEM showed a distinct cylindrical shape that differed from the cone shape of A. simplex. The protruded mucron could be used to identify A. typica L3 larvae in the future. A comparison of the ITS1-5.8S-ITS2 rDNA nucleotide sequences of these species revealed high blast scores with A. typica. Conclusively, it was confirmed that A. typica L3 are prevalent in threadfin breams from the Gulf of Thailand, and their morphological and molecular characters are something different from those of other anisakid larvae, including A. simplex and A. pegreffii. [ABSTRACT FROM AUTHOR]

Abstract: The rate of fish invasion into the Mediterranean Sea has increased in recent decades; collectively they have significant ecological and economic impacts in the eastern Mediterranean. One of this species is Japanese thread fin bream Nemipterus japonicus that gradually get abundance in the Egyptian Mediterranean coast bottom trawl catch. During 2011, monthly samples of N. japonicus caught off Abu Qir area, Alexandria-Egypt, were used to estimate some biological parameters of this immigrant species. Females were more in abundance than male in the catch deviated to smaller size than male. Spawning season extended from April to November with highest activities in July. Maximum observed age was 3years for both sexes with no significant difference between their lengths at age. Length-at-age was fitted to the Von Bertalanffy growth models. Present results of the Mediterranean Sea population showed lower biological (e.g. growth and longevity) condition comparing to original indo-pacific population. [Copyright &y& Elsevier]