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Morphological comparison for the dorsal fin of Chrysichthys auratus, Synodontis schall, and Synodontis serratus (Teleosti: Siluriformes) collected from the Lake Nasser and the River Nile, Egypt

Farrag Mahmoud M. S., Jawad Laith A., Park Joo M.

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 4

420--429

EN

The anatomy, growth, and differentiation of the dorsal fin spines of three catfish species collected from the Nile River and Lake Nasser. Egyptian waters are described, and terminology is suggested for their parts. Features of the dorsal fin spine that change with growth are also described. The results showed that in all species studied, the dorsal spine is an elongate, compressed, tapered, slightly arched, osseous structure, bearing a series of retrorse dentations along the anterior and posterior surfaces and has a sharp sagittate tip. The retrorse, anterior dentations are most pronounced in the upper third of the spine and gradually alter in form until they appear as a series of distinct notches on the basal third of the spine. The anterolateral surfaces of the dorsal spine are marked by numerous short, irregular, shallow, anastomosing, longitudinal furrows. In three species (C. auratus, S. schall, S. serratus), the posterior process is poorly developed and directed laterally in young individuals and well produced and directed posteriorly in older specimens. In S. schall and S. serratus, the posterior blocking process of the large specimens has a wavy edge, while in S. serratus, it is curved in young individuals and straight in larger specimens.

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Morphological asymmetry in two marine fish species Acanthopagrus arabicus (Family: Sparidae) and Planiliza klunzingeri (Family: Mugilidae), collected from brackish and freshwater environments in southern Iraq

Jawad Laith A., Al-Saboonchi Azhar A., Musa Zainab J., Nazal Azhar M., Al-Dirawi Ahmed M. H.

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 2

228--239

EN

Morphological asymmetry was analysed in two marine fish species Acanthopagrus arabicus and Planiliza klunzingeri,in brackish and freshwater habitats in southern Iraq. For bothspecies, specimens from the Shatt al-Arab River and Shatt al-Basrah Canal exhibited greater asymmetry values for snout length. In both locations examined, the levels of asymmetry of the physical traits increased as the fish grew. The high levels of asymmetry in the two fish species may be linked to heavy metal pollutants in the two aquatic environments studied.

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Biometric relation between body size and otolith size of Cyprinion kais and C. macrostomum collected from Tigris River, Şirnak Province, Türkiye

Dörtbudak Muhammed Yaşar, Jawad Laith A., Yalçin Hamza, Park Joo Myun

Oceanological and Hydrobiological Studies

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2023

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Vol. 52, No. 2

221-227

EN

One hundred and twenty asterisci were obtained from 30 specimens each of Cyprinion kais and Cyprinion macrostomum. Significant relationships between otolith mass and the three fish lengths (TL, SL, and FL) were attained for C. kais. Similar associations were obtained for OL and the three fish lengths of C. macrostomum. For C. kais,the highest in the relation between otolith mass, hereafter referred to as OM, and fish fork length, henceforth knownas FL (0.5894). The lowest coefficient of determination wasobserved between otolith width, hereafter called OW, and standard fish length, hereafter referred to as SL (0.2861). For C. macrostomum, the highest coefficient of determination was attained for the relation between OL and FL (0.7280) and the lowest for the relationship between OM and TL (0.1717).The analysis shows that evaluations of the body size of the two fish species investigated through biometric studies ofotoliths are trustworthy.

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Growth parameters of Poecilia latipinna (Lesueur, 1821) (Actinopterygii, Poeciilidae) : an introduced species in brackish water of Wadi Al-Bahayes (Oman)

Güçlü Salim Serkan, Al Jufaili Saud M, Jawad Laith A

Oceanological and Hydrobiological Studies

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2021

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Vol. 50, No. 3

269--277

EN

This work is one of the first studies on the growth of Poecilia latipinna outside its natural habitat. The objective of our study was to investigate the growth parameters of the population of P. latipinna, which is an alien species in Oman (Wadi Al-Bahayes). The population structure of P. latipinna in Wadi Al-Bahayes (Oman; 23°40′47″N; 58°11′36″E) was studied in June and August 2020, using 124 fish. In the course of this study, the number of individuals of each sex, age, weight and size composition were determined. In addition, the total length–weight relationship (LRW) was calculated, as well as the von Bertalanffy growth equation. The mean growth performance (phi prime) and the condition factor were calculated. Males accounted for 37.10% and females for 62.90% of the population. The length–weight relationship and the von Bertalanffy growth equation were W = 0.0214 × L2.7889 R2 = 0.9212, Lt = 11.46 (1 – e−0.127 (t + 2.71)) for males and Lt = 14.51 (1 – e−0.072 (t + 3.98)) for females. The mean growth performance and the condition factor were calculated as 1.22 for males and 1.18 for females and 1.54 for all specimens.