Hydrogeomorphic factors drive differences in otolith morphology in fish from the Nu‐Salween River. Issue 1 (13th August 2018)

• Record Type: Journal Article
• Authors: Ding, Liuyong; Tao, Juan; Ding, Chengzhi; Chen, Liqiang; Zhang, Chao; Xiang, Qianqian; Sun, Jie
• Is Part Of: Ecology of freshwater fish. Volume 28:Issue 1(2019)
• Page Start: 132
• Page End: 140
• Publication Date: 2018-08-13
• Subjects: acclimation -- functional adaptation -- longitudinal gradient -- phenotypic plasticity -- Schizothorax nukiangensis; Freshwater fishes -- Periodicals; Freshwater fishes -- Ecology -- Periodicals; Fisheries -- Periodicals; 597.092
• DOI: 10.1111/eff.12437
• Languages: English
• ISSNs: 0906-6691

Abstract

Abstract: Understanding the relationship between intraspecific phenotypic variation and habitat is fundamentally important to ecology and evolution. However, it is largely unknown whether the environment drives the morphological variation in riverine fish otoliths, which are potential phenotypic markers. In this study, we investigated morphological variations in the otoliths of an endemic Chinese fish ( Schizothorax nukiangensis Tsao) collected from seven sites with varying environmental gradients along the Nu ‐ Salween River. We compared morphological characters of S . nukiangensis otoliths among sampling sites and identified environmental sources of otolith morphological variation using multivariate regression trees and multiple factor analysis. Results showed that S . nukiangensis otoliths collected from different habitats were significantly different in morphology, mainly at the rostrum, excisura and posterior rim. Variations in otolith morphology (specifically the increase in otolith length) were predominantly governed by average river gradient; this might be a functional response to hydrogeomorphic conditions. Other environmental gradients (i.e., altitude, latitude and average annual temperature) played a minor role in otolith shape. This study highlighted the role of environmental factors in determining the otolith shape in riverine fish; thus, species and population discriminations based on otolith morphology should consider intraspecific variability.