番红砗磲外套膜颜色多态性及其与生长性状相关性研究

Colour Polymorphism of Tridacna crocea Mantle and Its Correlation with Growth Traits

本研究以南海西沙海域番红砗磲(Tridacna crocea)为实验对象,通过CSE-1成像色度检测分析系统和聚类分析方法研究其外套膜颜色多态性,同时,比较外套膜颜色与形态性状的相关性。结果显示,大部分番红砗磲外套膜颜色分布在蓝原色和红原色区域,少部分个体分布在绿原色区域,且偏亮绿色;番红砗磲外套膜颜色共聚为6个颜色类群,各类群间颜色色差均>15,其中,第4类深蓝色和第6类黄色色差最大,为74.68;第3类浅蓝色和第4类深蓝色色差最小,为18.98;番红砗磲外套膜颜色L、a、b值与壳高呈显著正相关(P<0.05),相关系数分别为0.2080、0.2210和0.2375。本研究结果可为砗磲资源保护和珊瑚礁生态系统恢复提供参考。

As one of the main members in coral reef ecosystems,giant clams have important economic and ecological value.The conspicuous,brightly coloured mantle shared by all giant clams is a unique feature distinct from other bivalve mollusks and plays an important role in energy harvesting and privacy protection.The boring giant clam Tridacna crocea is usually found at depths of 0.5~3.5 m and is one of the most colourful giant clam species.In this study,T.crocea from Xisha,South China Sea was used to study mantle colour polymorphism by CSE-1 imaging and colour-measuring system and cluster analysis.Moreover,the relationship between mantle colour and morphological traits of T.crocea was also studied.The results showed that the mantle colour of most T.crocea individuals was distributed in the blue and red primary regions,and only a few individuals showed colour distribution in the green primary and bright green regions.T.crocea were clustered into six colour groups(including brown,reddish brown,light blue,dark blue,green and yellow),and the colour differences between each group were>15,among which the difference between dark blue colour of the fourth type and yellow colour of the sixth type was the largest(DE=74.68),while the difference between light blue of the third type and dark blue of the fourth type was the smallest(DE=18.98).The L,a,and b values of T.crocea mantle had significant positive correlations with shell height(P<0.05);the correlation coefficients were 0.2080,0.2210,and 0.2375,respectively.This study provided a basic reference for the conservation of giant clam resources and the recovery of coral reef ecosystems.