TY - JOUR T1 - Quantitative assessment of gula pigmentation in Chironomus riparius (Diptera: Chironomidae) TT - Chironomus riparius (Diptera: Chironomidae)’ta gula pigmentasyonunun nicel değerlendirilmesi AU - Akyıldız, Gürçay Kıvanç PY - 2026 DA - February Y2 - 2025 DO - 10.12714/egejfas.43.1.05 JF - Ege Journal of Fisheries and Aquatic Sciences JO - EgeJFAS PB - Ege University WT - DergiPark SN - 2148-3140 SP - 40 EP - 47 VL - 43 IS - 1 LA - en AB - Chironomids (Diptera: Chironomidae) are among the most abundant and ecologically significant invertebrates in freshwater ecosystems. Within this group, the genus Chironomus poses considerable taxonomic challenges due to its high number of cryptic species, especially at the larval stage. Larval identification traditionally relies on qualitative morphological characters, such as the pigmentation of the gula. However, the subjective nature of these observations limits reproducibility and diagnostic accuracy. This study provides a quantitative assessment of gula pigmentation variation among Chironomus riparius larvae derived from a single egg mass. Image processing techniques were applied to convert color traits into measurable parameters, enabling objective analysis of pigmentation intensity, distribution, and optical properties. Digital quantification revealed significant intraspecific variation in gula pigmentation, even among genetically identical larvae reared under uniform laboratory conditions. These results underscore the potential of digital image analysis to improve the precision, objectivity, and reproducibility of morphological identification in chironomids. This methodological framework contributes to the standardization of qualitative traits for broader use in ecological and systematic research. KW - Chironomus riparius KW - gula pigmentation KW - image analysis KW - morphometry KW - non-biting midges KW - phenotypic variation N2 - Chironomidler (Diptera: Chironomidae), tatlı su ekosistemlerinde en bol bulunan ve ekolojik açıdan en önemli omurgasız gruplarından biridir. Bu grup içerisinde yer alan Chironomus cinsi, özellikle larva evresinde çok sayıda kriptik tür içermesi nedeniyle önemli taksonomik güçlükler barındırmaktadır. Larvaların tanımlanması geleneksel olarak gula pigmentasyonu gibi nitel morfolojik karakterlere dayanmaktadır. Ancak bu tür gözlemlerin öznel yapısı, tekrarlanabilirliği ve tanısal doğruluğu sınırlandırmaktadır. Bu çalışmada, tek bir yumurta paketinden elde edilen Chironomus riparius larvalarında gula pigmentasyonundaki varyasyon nicel olarak değerlendirilmiştir. Renk özelliklerini ölçülebilir parametrelere dönüştürmek amacıyla görüntü işleme teknikleri uygulanmış; böylece pigmentasyon yoğunluğu, dağılımı ve optik özelliklerinin nesnel biçimde analiz edilmesi sağlanmıştır. Sayısal analizler, genetik olarak özdeş ve kontrollü laboratuvar koşullarında yetiştirilen larvalar arasında dahi gula pigmentasyonunda anlamlı tür içi varyasyon bulunduğunu ortaya koymuştur. Elde edilen bulgular, dijital görüntü analizinin chironomidlerde morfolojik tanımlamanın doğruluğunu, nesnelliğini ve tekrarlanabilirliğini artırma potansiyelini vurgulamaktadır. Sunulan bu metodolojik yaklaşım, nitel karakterlerin standartlaştırılmasına katkı sağlayarak ekolojik ve sistematik çalışmalarda daha geniş kullanım olanağı sunmaktadır. CR - Abashy, M.M. (2005). Culture of chironomid larvae (Insecta- Diptera Chironomidae) under different feeding systems. Egyptian Journal of Aquatic Research, 31, 403–418. 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