Cryptic variation in insect female genitalia: establishment and applications of their observational techniques

动物内生殖器与其他形态特征相比，一般表现出较快的进化速度。然而，与雄性生殖器的种间差异相比，雌性生殖器通常由柔软的结构组成，没有明显的标志，由于观察困难而受到较少关注。本研究利用不同昆虫类群的内连接词样本，探索了检测和描述雌性生殖器性状差异的有效方法。因此，苯甲醇和苯甲酸苄酯（BABB）的混合物已被证明是非常有效的，使昆虫外骨骼透明。该方法显示，女性生殖器通常在其柔软部分显示出相当大的结构多样性，对应于物种特异性的男性生殖器。实验表明，雄性和雌性生殖器之间的结构匹配降低了雌性的交配成本，例如由交配创伤和其他机制引起的交配成本。

Animal genitalia of internal fertilizers generally show a rapid evolutionary rate compared with other morphological characters. However, compared to interspecific diversities in male genitalia, female genitalia, which usually consist of soft structures without conspicuous landmarks, received less attention because of the difficulty of observation. In this study, efficient methods to detect and describe diversities in female genital traits were explored using in-copula samples of various insect taxa. As the result, a mixture of benzyl alcohol and benzyl benzoate (BABB) has been proven to be highly effective to make insect exoskeleton transparent. The method revealed that female genitalia generally show a sizable structural diversity in their soft parts corresponding to the species-specific male genitalia. Experiments showed that the structural fitting between male and female genitalia reduces mating costs for females such caused by copulatory wounding and other mechanisms.