萼花臂尾轮虫种复合体内三个姐妹种的形态差异

Morphometric differences among three sibling species in Brachionus calyciflorus species complex

应用单因子方差分析和判别分析方法,分别比较了采自芜湖市3个自然水体的萼花臂尾轮虫种复合体内3个姐妹种(分别以克隆HE1和HE5、克隆HE3和SE1、克隆LE9为代表)的成体和幼体的形态差异。结果表明,克隆HE3成体的各形态参数均最小,而克隆HE1和LE9成体的各形态参数间无显著的差异;克隆HE1和HE3幼体的前中棘刺间距离和后侧棘刺长度、克隆LE9和HE1幼体的前侧棘刺间距离以及前中棘刺和侧棘刺间距离均无显著性差异,轮虫幼体的其它形态参数均以克隆LE9最长,克隆HE1次之,克隆HE3最短。对克隆HE1、HE3和LE9幼体有明显差异的形态参数所作的分布图显示,它们的分布区有很高程度的重叠。以判别分析建立的判别函数对3姐妹种成体的综合判别率中形态分析Ⅰ为47.8%,形态分析Ⅱ为55.6%;对3姐妹种幼体的综合判别率中形态分析Ⅰ和Ⅱ均为71.1%;两种形态分析对克隆HE1判别准确率均较低,分别为0-76.7%和0-74.2%;依据形态特征无法准确甄别萼花臂尾轮虫姐妹种。

Morphometric differences of neonates and adults of clone HE1 and HE5,clone HE3 and SE1,and clone LE9 which respectively represented three sibling species in Brachionus calyciflorus species complex collected from three water bodies in Wuhu City were compared by means of one-way ANOVA and discriminant analysis.The results showed that all morphometric parameters of clone HE3 adult were the smallest,but those of the other two clones were similar.The distance between the two anterior medial spines and the posterior lateral spine length of clone HE1 and HE3 neonates as well as the distances between the two anterior lateral spines and between anterior lateral and medial spines of clone LE9 and HE1 neonates were similar,but all the other morphometric parameters were the longest for clone LE9 neonates but the shortest for clone HE3 neonates.The distribution regions of morphometric parameters with statistical differences were extensive overlap.Discriminant analysis showed that the total discriminant accuracies of the discriminant functions for the adults of the three clones in morphometric analysisⅠand Ⅱ was 47.8% and 55.6%,respectively,while those of neonates were both 71.1%.The identification accuracies based on morphometric analysis Ⅰ and Ⅱ for clone HE1 were low and 0-76.7% and 0-74.2%,respectively.The morphometric characteristics used in this study is unsuitable to accurately identify sibling species in Brachionus calyciflorus species complex.