In predators an ontogenetic trophic shift includes change from small to large prey of several different taxa. In myrmecophagous predators that are also mimics of ants, the ontogenetic trophic shift should be accompanied by a parallel mimetic change. Our aim was to test whether ant-eating jumping spider, Mexcala elegans, is myrmecomorphic throughout their ontogenetic development, and whether there is an ontogenetic shift in realised trophic niche and their mimetic models. We performed field observations on the association of Mexcala with ant species and investigated the natural prey of the ontogenetic classes by means of molecular methods. Then we measured the mimetic similarity of ontogenetic morphs to putative mimetic models. We found Mexcala is an inaccurate mimic of ants both in the juvenile and adult stages. During ontogenesis it shifts mimetic models. The mimetic similarity was rather superficial, so an average bird predator should distinguish spiders from ants based on colouration. The realised trophic niche was narrow, composed mainly of ants of different species. There was no significant difference in the prey composition between ontogenetic stages. Females were more stenophagous than juveniles. We conclude that Mexcala is an ant-eating specialist that reduces its prey spectrum and shifts ant models during ontogenesis.

中文翻译：

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在实现的营养生态位中，没有个体发生变化，但是在以蚂蚁为食的蜘蛛中的贝茨模拟中。

在捕食者中，个体发生的营养转变包括几种不同分类单元的猎物从小到大的变化。在也模仿蚂蚁的食肉性捕食者中，个体的营养变化应伴随着类似的模拟变化。我们的目的是测试以蚂蚁为食的跳跃蜘蛛，Mexcala elegans，在整个个体发育过程中是否是同种异形的，以及在已实现的营养生态位及其模拟模型中是否存在个体发生的转变。我们对梅克斯卡拉与蚂蚁物种的关系进行了实地观察，并通过分子方法研究了个体发育类别的自然猎物。然后，我们测量了本体形态与模拟模型的模拟相似性。我们发现Mexcala在幼年期和成年期均不准确地模拟蚂蚁。在本体形成过程中，它会改变模拟模型。拟态相似性相当肤浅，因此一般的鸟类捕食者应根据颜色将蜘蛛与蚂蚁区分开。实现的营养生态位很窄，主要由不同物种的蚂蚁组成。个体发育阶段之间的猎物组成没有显着差异。女性比青少年更食管狭窄。我们得出的结论是，Mexcala是一种蚂蚁食用专家，可以减少其猎物谱并在本体形成过程中改变蚂蚁模型。女性比青少年更食管狭窄。我们得出的结论是，Mexcala是一种蚂蚁食用专家，可以减少其猎物谱并在本体形成过程中改变蚂蚁模型。女性比青少年更食管狭窄。我们得出的结论是，Mexcala是一种蚂蚁食用专家，可以减少其猎物谱并在本体形成过程中改变蚂蚁模型。