Quantitative assessment of gula pigmentation in Chironomus riparius (Diptera: Chironomidae)

Gürçay Kıvanç Akyıldız

doi:10.12714/egejfas.43.1.05

EN TR

Quantitative assessment of gula pigmentation in Chironomus riparius (Diptera: Chironomidae)

Abstract

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.

Keywords

Chironomus riparius (Diptera: Chironomidae)’ta gula pigmentasyonunun nicel değerlendirilmesi

Öz

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.

Anahtar Kelimeler

Supporting Institution

This research has not received a specific grant, fund or other support from any funding agency in the public, commercial, or not-for-profit sectors.

Project Number

No Project Number

Ethical Statement

No specific ethical approval was necessary for this study.

Thanks

This research has not received a specific grant, fund or other support from any funding agency in the public, commercial, or not-for-profit sectors.

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Details

Primary Language

English

Subjects

Hydrobiology , Freshwater Ecology , Aquaculture and Fisheries (Other)

Journal Section

Research Article

Authors

Gürçay Kıvanç Akyıldız ^*
0000-0001-9610-8443
Türkiye

Publication Date

February 18, 2026

Submission Date

October 27, 2025

Acceptance Date

December 29, 2025

Published in Issue

Year 2026 Volume: 43 Number: 1

DOI

https://doi.org/10.12714/egejfas.43.1.05

IZ

https://izlik.org/JA86RC79UC

Cite

RIS / Bibtex

APA

Akyıldız, G. K. (2026). Quantitative assessment of gula pigmentation in Chironomus riparius (Diptera: Chironomidae). Ege Journal of Fisheries and Aquatic Sciences, 43(1), 40-47. https://doi.org/10.12714/egejfas.43.1.05