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Background. Dipturus oxyrinchus (Linnaeus, 1758) is a common skate in Syrian elasmobranch fishery. This species is listed as an Endangered cartilaginous species on the International Union for the Conservation of Nature (IUCN) Red List. Although heavily exploited, until now, no study has been performed on this skate along the Syrian coast in the Levantine basin. This study focuses on the determination of the reproductive period, size at maturity and fecundity of D. oxyrhinchus. Materials and methods. Total length and total weight were determined for 249 specimens of the longnosed skate, captured off Syrian coast. Skates collected were measured and weighed according to standard procedures. Based on the acquired measurements the following relations were determined: disc width-total weight (DW-TW), total weight-total length (TW-TL), total weight-disc width (TW-DW), and total length-disc width (TL-DW). Median size (TL 50) at maturity was estimated according to commonly accepted methods. Hepatosomatic index (HSI) and gonadosomatic index (GSI) were calculated for males and females. The proportion of the occurrence of developmental stages were noted seasonally. Ovarian fecundity was calculated based on ripe follicles in both ovaries of mature females. Fecundity, expressed as annual egg production per female. Tests for significance (P < 0.05) were performed by using ANOVA, Student t-test, and the chi-square test. In the relations TW-TL and TW-DW, comparisons of curves were carried out by using ANCOVA Results. The observed sex ratio was 58.2% ÷ 40.2% (female ÷ male). Mean body measurements of females (n = 14) were slightly higher than males (n = 8). The total length of females ranged from 34.1 to 100.0 cm and males from 34.5 to 81.6 cm. The total length-total weight, disc width-total weight, and total length-disc width relations were TW = 0.0009TL 3.35 and TW = 0.0033DW 3.34 and DW = 0.6894TL + 0.281, respectively, for all sexes combined. Median size (TL 50) at maturity were estimated as TL 50 = 79.5 cm for females (n = 149) and TL 50 = 70.9 cm for males (n = 100). This species had a continuous reproductive cycle. Fecundity was estimated between 50 and 100 egg cases per year. Conclusion. Information on the reproduction of D. oxyrinchus may allow the decision makers to set appropriate catch limits based on biological reference points, and serves as a baseline in the event of increasing exploitation rates. Especially, this information showed that a possible nursery area maybe established in the Syrian marine waters.

Cartilaginous fishes off the Syrian coast have not been studied systematically as yet. To date, fortyfour chondrichthyans species [1, 2, 3, 4, 5, 6] were recorded in Syrian coast. In the Syrian marine waters, information related with the biology, fishery, landings, distribution and abundance of shark populations is scarce or non-existent. There were few studies interested in species survey and taxonomy [1, 2], species biology [7, 8, 9]. Whereas there were no studies on landings, distribution, abundance and structure of shark populations in this area. Chondrichthyans are vulnerable to overexploitation. Globally, lack of accurate catch data (due to under reporting, lack of by catch recording, poor species identification and species wise catch data, illegal fishing etc.) makes assessment and management of chondrichthyans exploiting difficult, which is a major concern. This issue was addressed by Convention on international Trade in Endangered Species (CTES) in 1994, which requested contracting parties to collect biological and trade information on sharks taken in their fisheries. This was reiterated by FAO in 1999 by its adoption of International Plan of Action (IPOA) for Conservation and management of sharks. At present, only a few countries have management and monitoring programs for chondrichthyans. Sharks have experienced increased demand in recent years due to rise of bony fish price and the request increasing on fish; despite Syria has no targeted sharks fishery. Although the diversity of cartilaginous fish, there are no studies have been undertaken to determine the biological characteristics of the shark catches or its ability to withstand this increased exploitation, The present study was undertaken as a first step to remedying this situation, which aimed to provide the first detailed assessment of the compositions and abundances of shark in Syrian marine waters. The length structure, sex compositions and possible nursery places of abundant and common species were determined.

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This paper reports the first record of the Emperor angelfish Pomacanthus imperator (Bloch, 1787) from the Syrian coast. The specimen was caught by trap at depth of 15 m on 18 February 2018. The fish measured 272 mm in total length, and weighted 1349 g The record represents the second sighting of this species in the Levantine basin, but since it is based on a single isolated individual there is no evidence that the species has established a population in Syrian waters. Therefore at present P. imperator must be regarded as a casual species.