Ground beetles in multiple species vary greatly in the expression of the shape on sexual traits, resulting in a sexual shape dimorphism as a consequence of sexual selection differences. The present research focuses on the study of inter and intrasexual sexual shape dimorphism of two generalist genera of ground beetles Pterostichus and Carabus. Geometric morphometric methods were applied to five generalist species of ground beetles Carabus exaratus, C. granulatus, Pterostichus melanarius, P. niger, and P. oblongopunctatus and several multivariate analyses were applied for two different traits, abdomen and elytra. Three of the five species analyzed showed high levels of sex-based shape dimorphism. However, the most generalist species, P. melanarius and P. oblongopunctatus, did not evidence shape-based sexual dimorphism differentiation in both of the analyzed traits, as statistically confirmed based on the permutation of pairwise comparison of the Mahalanobis distances of a sex–species classifier. It is generally known that environmental stress in natural populations can affect the fitness expression, principally related to sexual fecundity, being that this pattern is more evident in non-generalist species. In our results, the contrary pattern was found, with the absence of sexual shape dimorphism for two of the three generalist species analyzed. On the other hand, the interspecies shape variation was clearly identified using principal component analysis of both of the analyzed traits. Finally, this research is the first to analyze the relationship between sexual shape dimorphism in Russian ground beetles, evidencing the lack of understanding of the mechanism underlying the sexual dimorphism, especially in species living in extreme environments.

中文翻译：

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在俄罗斯测量普通甲虫的种间和种内性别形状二态性和体型变异。

多个物种中的地面甲虫在性状上的形状表达差异很大，由于性别选择差异而导致性状二态性。本研究的重点是研究地面甲虫Pterostichus和Carabus的两个通才属的性别间和性别异型性。几何形态方法应用于地面5个通才物种金龟大步甲exaratus，C. granulatus，Pterostichus melanarius，P.曲霉，和P. oblongopunctatus 对几个不同的性状（腹部和鞘翅）进行了多变量分析。分析的五个物种中的三个显示出高水平的基于性别的形状二态性。但是，最笼统的物种是P. melanarius 和P. oblongopunctatus， 并没有根据两个被分析的性状来证明基于形状的性二态分化，这是根据性别一类分类器的马氏距离的成对比较的排列进行统计证实的。众所周知，自然种群中的环境压力会影响适应度的表达，这主要与性繁殖力有关，因为这种模式在非一般物种中更为明显。在我们的研究结果中，发现了相反的模式，在所分析的三个通才物种中，有两个没有性别形状二态性。另一方面，通过对两个分析特征的主成分分析，可以清楚地识别出种间形状的变化。最后，这项研究是第一个分析俄罗斯地面甲虫性状二态性之间关系的研究，