SUMMARY:Aphanius dispar (Rüppell, 1829) is a common marine-euryhaline teleost fish in the Near East that has undergone considerable intraspecific differentiation. Otolith morphology is used to analyse the diversity within A. dispar in the Gulf of Oman (Sea of Oman) and the Persian Gulf. A total of 134 individuals from lagoons and inland habitats of Oman, the United Arab Emirates and southern Iran are analysed. The results revealed that otolith traits that are under genetic control are strikingly different from those that are under the influence of environmental factors. A clear spatial structure of the populations is detectable, suggesting that the environmental flexibility of A. dispar, vicariance events during the last glacial maximum (21000-18000 BP), dispersal in the course of the Early Holocene sea-level rise, and Holocene to presentday interruption of gene flow at the Strait of Hormuz have shaped the intraspecific differentiation of A. dispar. These factors may also be responsible for diversification within other marine-euryhaline fishes in the Near East and Mediterranean Sea, and thus the findings can contribute to successful conservation management.

The sagittae mass asymmetry was studied in the teleost Lutjanus bengalensis and it is calculated as the difference between the mass of the right and left paired otoliths divided by average otolith mass. As in the case of other symmetrical fish species, the result of the present study showed that the absolute value of sagittae mass asymmetry (X) in L. bengalensis does not depend on fish length and otolith growth rate. On the other hand, the absolute value of otolith mass asymmetry is increased with the fish length. The value of sagittae mass asymmetry falls between -0.2 and +0.2. Özet: Umman Denizi, Muscat Şehrinde Lutjanus Bengalensis (Family: Lutjanidae) Otolit Kütle Asimetrisi Üzerine Bir çalışmaBu çalışmada; teleost Lutjanus bengalensis'in kütle asimetrisi, sağ ve sol otolit çiftlerinin kütleleri, ortalama otolit kütlesine bölümü ile hesaplanarak çalışılmıştır. Diğer simetrik balık türlerinde olduğu gibi, bu çalışmada da sagittae kütle asimetrisinin mutlak değeri (X)'nin L. Bengalensis türünde de balığın boyuna ve otolit büyüme oranına bağlı olmadığı görülmüştür. Diğer yandan mutlak otolit kütle asimetrisinin boy uzadıkça artmıştır. Sagittae kütle asimetri değeri -0.2 ile +02 arasında hesaplanmıştır.

We employed molecular systematic analysis based on mitochondrial D-loop sequences to identify two specimens of ocean sunfish from Omani coastal waters that had previously been identified morphologically as Mola mola (Linnaeus, 1758) and M. ramsayi (Giglioli, 1883). Of the three molecular species that are recognized globally, Mola sp. A, Mola sp. B, and Mola sp. C, we confirmed that both specimens from Oman are Mola sp. A. This result suggested a broader distribution of this species than had ever been thought, but it also revealed a discrepancy between morphological and genetic characters in Mola taxonomy. We reexamined the morphology of the two specimens from Oman to clarify the extent to which the key morphological features correspond with molecular genetic identifications, and discovered errors in the original reports on both specimens.

The first record of the southern ocean sunfish Mola ramsayi in Omani waters is reported based on a single 916 mm total length specimen found stranded on the coasts of Sur City 193 km south of the Omani capital Muscat, 22835 ′ 10.22 ′′ N 59830 ′ 18.91 ′′ E. This account also represents the third northernmost record of a south ocean sunfish in the Indian Ocean. Morphometric and meristic data are provided and compared with those of 5 specimens caught off United Arab Emirates, Brazil and India. The southern ocean distribution of M. ramsayi is corrected in this report.

The present paper reports the first record of one antennarid species from the Gulf of Oman and the second record of another frogfish from the Arabian Sea coasts of Oman. The record of Antennarius coccineus is a north-eastern extension of its distribution in Omani waters. Antennarius indicus was recorded for the second time from the Arabian Sea coasts of Oman.