雄性生殖器的形态计量学分析通常用于区分甲虫的属和种,蝴蝶,和苍蝇,但很少用于蚂蚁,大多数形态计量学分析都集中在工人种姓的外部形态上。在这项工作中,我们对马达加斯加的男性生殖器进行了线性形态学分析,以区分Monomorium和Syllophopsis。对于80个样本,我们测量了10个形态特征,尤其是在paramere上,Volsella,和侧翼。从线性测量中获得了三个数据集:平均值(原始数据),字符的比率(比率数据),和去除异速变化(RAV数据)。以下定量方法被应用于这些数据集:层次聚类(沃德方法),无约束排序方法,包括主成分分析(PCA),非公制多维缩放分析(NMDS),线性判别分析(LDA),和条件推理树(CITs)。统计分析结果表明,该比率被证明是属水平分化的最有效方法。然而,RAV方法表现出各属之间的重叠。同时,与比率和RAV方法相比,原始数据在物种水平上促进了更细微的区别。TheCITs表明,valviceps(SeL)的齿长度与参数高度(PaH)的比率有效地区分了属,并确定了物种水平分化的关键变量。总的来说,这项研究表明,男性生殖器的线性形态分析是分类划界的有用数据来源。
Morphometric analyses of male genitalia are routinely used to distinguish genera and species in beetles, butterflies, and flies, but are rarely used in ants, where most morphometric analyses focus on the external morphology of the worker caste. In this work, we performed linear morphometric analysis of the male genitalia to distinguish Monomorium and Syllophopsis in Madagascar. For 80 specimens, we measured 10 morphometric characters, especially on the paramere, volsella, and penisvalvae. Three datasets were made from linear measurements: mean (raw data), the ratios of characters (ratio data), and the Removal of Allometric Variance (RAV data). The following quantitative methods were applied to these datasets: hierarchical clustering (Ward\'s method), unconstrained ordination methods including Principal Component Analysis (PCA), Non-Metric Multidimensional Scaling analyses (NMDS), Linear Discriminant Analysis (LDA), and Conditional Inference Trees (CITs). The results from statistical analysis show that the ratios proved to be the most effective approach for genus-level differentiation. However, the RAV method exhibited overlap between the genera. Meanwhile, the raw data facilitated more nuanced distinctions at the species level compared with the ratios and RAV approaches. The CITs revealed that the ratios of denticle length of the valviceps (SeL) to the paramere height (PaH) effectively distinguished between genera and identified key variables for species-level differentiation. Overall, this study shows that linear morphometric analysis of male genitalia is a useful data source for taxonomic delimitation.