Scoliosis deformity in Alburnus escherichii, an endemic freshwater leuciscid (Teleostei) from the Sakarya River Basin, Türkiye: morphological description and a case study

Zafer Alpaslan; Salim Serkan Güçlü; Atilla Arslan; Laith A. Jawad

doi:10.26881/oahs-2026.1.09

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Scoliosis deformity in Alburnus escherichii, an endemic freshwater leuciscid (Teleostei) from the Sakarya River Basin, Türkiye: morphological description and a case study

Oceanological and Hydrobiological Studies

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By: Zafer Alpaslan , Salim Serkan Güçlü , Atilla Arslan and Laith A. Jawad

Open Access

|Apr 2026

Abstract

In this study, a total of eight Alburnus escherichii individuals were captured from the Sakarya River Basin, Türkiye. In only one of these specimens, a skeletal deformity (scoliosis) was observed and examined. The scoliosis affected the caudal region of the vertebral column, presenting two curves originating posterior to the dorsal fin. These curves formed two angles, measuring 135° and 152°. Externally, at the point of scoliosis onset, the body contour and lateral line scales were deformed. The deformity affected the posterior part of the dorsal fin and the anterior part of the anal fin. Additionally, the neural and hemal spines of the ultimate abdominal vertebra were slightly deformed. This study discusses the possible causes of scoliosis and the significance of reporting such deformities for anatomical and broader ichthyological research.

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DOI: https://doi.org/10.26881/oahs-2026.1.09 | Journal eISSN: 1897-3191 | Journal ISSN: 1730-413X

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Language: English

Submitted on: Jan 16, 2026

Accepted on: Mar 23, 2026

Published on: Apr 15, 2026

Published by: University of Gdańsk

In partnership with: Paradigm Publishing Services

Publication frequency: 4 issues per year

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© 2026 Zafer Alpaslan, Salim Serkan Güçlü, Atilla Arslan, Laith A. Jawad, published by University of Gdańsk
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

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