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Laith Jawad, Okan Akyol and Cemil Saǧlam

Abstract

The incidence of severe consecutive repetition of lordosis-kyphosis involving three flexions was reported in a specimen of the atherinid fish Atherina boyeri Risso. The values for the angles lay between the lines passing through the sides of the vertebral column and enclosing the curvatures, and the depth of the curvatures of the angles was obtained. Also, the ratio of the vertebral column to the fish total length of deformed and normal specimens of this species was calculated. Possible causes for these anomalies are discussed.

Open access

Laith A. Jawad and Muhammad I. G. Al-Janabi

Abstract

Thirteen morphometric characters of catfish Silurus triostegus were studied from three localities on the Tigris and Shatt al-Arab rivers, Iraq. Monthly samples revealed no significant differences between genders. Positive allometric growths for all morphometric characters studied were observed. This study gives information to fishery biologists about morphometric characters of S. triostegus from the Tigris and Shatt al-Arab rivers to assist in planning of conservation strategies for this fish species.

Open access

Laith A. Jawad, Alessandro Ligas and Muhammad I.G. Al-Janabi

Abstract

Variation in the numbers of pectoral fin spines and rays, pelvic fin rays, gill rakers on the first gill arch, anal fin rays, and the number of vertebrae of Silurus triostegus Heckel were examined in specimens from 16 localities that span its entire distribution range in the Tigris, Euphrates, and Shatt al-Arab rivers in Iraq. The mean number of the six meristic traits increases toward high latitudes with maximum and minimum values in the north and south of Iraq. Based on cluster analysis and PCA, the Mesopotamian river samples were clearly separated into three distinct groups. The upper Tigris populations were isolated from those of the middle and southern populations of this river and from those of the Euphrates River. Possible reasons for such differentiation among populations are discussed, and the integration of research on this species among the countries neighboring Iraq is required.

Open access

Laith A. Jawad, Mustafa Ibrahim and Baradi Waryani

Abstract

These case studies endeavor to report incidences of caudal fin deformities in several commercial fishes living in natural populations in the Saudi Arabian coastal waters of the Arabian Gulf. Two groups of anomalies were observed, slight and severe. The carangid species, Parastromateus niger (Bloch) and the soleid species, Euryglossa orientalis (Bloch & Schneider), had slight cases of caudal fin abnormalities, while the species Oreochrromis mossambicus (Peters), Epinephelus stoliczkae (Day), Diagramma pictum (Thunberg), Cephalopholis hemistiktos (Rüppell), Lethrinus nebulosus (Forsskål), and Lutjanus sanguineus (Cuvier) had severe deformities. The abnormalities were assessed by morphological diagnosis. None of the cases was fatal as they occurred in adult individuals. The possible causes for these deformities as well as the suitability of this kind of case study for environmental monitoring are discussed. Further studies should be conducted from the perspective of pollution.

Open access

Laith A. Jawad, Abbas J. Al-Faisal and Mustafa Al-Mukhtar

Abstract

A severe coalescence involving 11 thoracic and 11 caudal vertebrae was noticed in the posterior part of the thoracic and anterior part of the caudal regions of the vertebral column of the abnormal specimen of Luciobarbus xanthopterus collected from Al-Huwaza Marsh, Maisan Province, South of Iraq. Also, other minor anomalies were noticed in the specimen in question. Probably, genetic and epigenetic causes may be implicated in this anomaly.