A comparative analysis of morphometric and meristic traits of endangered (Salmo opimus Turan, Kottelat and Engin, 2012 and Salmo plathycephalus Behnke, 1968) and at risk (Salmo okumusi Turan, Kottelat and Engin, 2014) trout species

Abstract

This study examines interspecies differentiation by comparing the morphometric and meristic characteristics of two endangered trout species (Salmo opimus Turan, Kottelat and Engin, 2012 and Salmo plathycephalus Behnke, 1968) and a species with the potential to be endangered (Salmo okumusi Turan, Kottelat and Engin, 2014). The research was conducted between 2014 and 2016 in the upper tributaries of the Ceyhan, Seyhan, and Euphrates basins in Türkiye. A total of 25 morphometric and 24 meristic characters were examined, and the measurements influencing interspecies differentiation were analyzed using the Random Forest model. The results indicate that S. plathycephalus exhibits significant differentiation in metric characteristics. In particular, variables such as predorsal length, head length, and body height are key distinguishing factors for this species. Among the meristic traits, the number of red spots and black markings on the operculum are critical for species identification. This study enhances understanding of species’ environmental adaptations and informs conservation strategies, laying a foundation for sustainable management. Future research should focus on habitat conservation efforts.

Keywords

• Endangered trout species
• morphometric traits
• meristic traits
• interspecies differentiation
• conservation biology

Tehlike Altındaki (Salmo opimus Turan, Kottelat ve Engin, 2012 ve Salmo plathycephalus Behnke, 1968) ve (Salmo okumusi Turan, Kottelat ve Engin, 2014) Alabalık Türlerinin Morfometrik ve Meristik Özelliklerinin Karşılaştırmalı Analizi

Öz

Bu çalışma, iki tehlike altındaki alabalık türünün (Salmo opimus Turan, Kottelat ve Engin, 2012 ve Salmo plathycephalus Behnke, 1968) ve tehlike altında olma potansiyeline sahip bir türün (Salmo okumusi Turan, Kottelat ve Engin, 2014) morfometrik ve meristik özelliklerini karşılaştırarak türler arası farklılaşmayı incelemektedir. Araştırma, 2014-2016 yılları arasında Türkiye'deki Ceyhan, Seyhan ve Fırat havzalarının yukarı kollarında yürütülmüştür. Toplam 25 morfometrik ve 24 meristik karakter incelenmiş ve türler arası farklılaşmayı etkileyen ölçümler Random Forest modeli kullanılarak analiz edilmiştir. Sonuçlar, S. plathycephalus'un metrik özelliklerde önemli bir farklılaşma sergilediğini göstermektedir. Özellikle predorsal uzunluk, baş uzunluğu ve vücut yüksekliği gibi değişkenler bu tür için temel ayırt edici faktörlerdir. Meristik özellikler arasında, operkulumdaki kırmızı nokta ve siyah işaretlerin sayısı tür tanımlaması için kritik öneme sahiptir. Bu çalışma, türlerin çevresel adaptasyonlarının anlaşılmasını geliştirmekte ve koruma stratejilerine bilgi sağlayarak sürdürülebilir yönetim için bir temel oluşturmaktadır. Gelecekteki araştırmalar, habitat koruma çalışmalarına odaklanmalıdır.

Anahtar Kelimeler

• Nesli tükenmekte olan alabalık türleri
• morfometrik özellikler
• meristik özellikler
• türler arası farklılaşma
• koruma biyolojisi

Kaynakça

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