Izquierdo M A, Dederichs T M, Cargnelutti F, Michalik P
Facultad de Ciencias Exactas, Físicas y Naturales, Departamento de Diversidad Biológica y Ecología, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina.
Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Laboratorio de Biología Reproductiva y Evolución, Instituto de Diversidad y Ecología Animal (IDEA), Córdoba, 5000, Argentina.
R Soc Open Sci. 2023 May 31;10(5):230263. doi: 10.1098/rsos.230263. eCollection 2023 May.
The male genitalia of pholcid spiders, which is one of the most species-rich spider families, are characterized by a procursus, which is a morphologically diverse projection of the copulatory organ. It has been shown that the procursus interacts with the female genitalia during copulation. Here, we investigate the function of the procursus in , a species belonging to the early branched and understudied subfamily Ninetinae, using behavioural and morphological data. Although many aspects of the copulatory behaviour of follow the general pattern described for the family, males use only one pedipalp during each copulation. Based on our micro-CT analysis of cryofixed mating pairs using virgin females, we can show that the long and filiform procursus is inserted deeply into the unpaired convoluted female spermatheca, and the intromittent sclerite, the embolus, is rather short and stout only reaching the most distal part of the female sperm storage organ. Histological data revealed that sperm are present in the most proximal part of the spermatheca, suggesting that the procursus is used to allocate sperm deeply into the female sperm storage organ. This represents the first case of a replacement of the sperm allocation function of the intromittent sclerite in spiders.
幽灵蛛是物种最为丰富的蜘蛛家族之一,其雄性生殖器的特点是有一个插入器,这是交配器官在形态上的多样化突出结构。研究表明,插入器在交配过程中与雌性生殖器相互作用。在此,我们利用行为学和形态学数据,对幽灵蛛科早期分支且研究较少的九眼蛛亚科中的一个物种的插入器功能展开研究。尽管该物种交配行为的许多方面遵循该家族所描述的一般模式,但雄性在每次交配时仅使用一侧触肢。基于我们对使用未交配过的雌性冷冻固定交配配对的显微CT分析,我们可以表明,细长丝状的插入器深深插入未配对的盘绕状雌性受精囊,而插入性骨片(栓)相当短且粗壮,仅到达雌性精子储存器官的最远端部分。组织学数据显示,精子存在于受精囊的最近端部分,这表明插入器用于将精子深入分配到雌性精子储存器官中。这代表了蜘蛛中插入性骨片精子分配功能被替代的首例情况。