Quantifying the effects of drilling predation on juvenile and adult gastropods is important for understanding the paleoecology of communities. Although numerous studies have examined predation on adult shells, virtually no reports cover juvenile specimens. We compare predation frequency and prey effectiveness between juvenile and adult gastropods in a Pliocene assemblage from the eastern Pacific of Mexico. Evidence of predation in the sample was confirmed by the presence of drilling in the shells, ascribed to Oichnus simplex Bromley, 1981 and O. paraboloides Bromley, 1981, which showed active predation by caenogastropods. The occurrence of drilling gastropods in the same locality reveals the possible predators as naticids (Polinices intermeratus (Philippi, 1853), and Natica broderipiana Récluz, 1844) and muricids (Eupleura vokesorum Herbert, 2005 and Thypina sp.). Some differences were found in predatory patterns between drilling gastropods, naticids drilled at a higher frequency than muricids in adults, while the opposite occurs in juveniles. Prey Effectiveness (PE) values were 0.00 for juveniles and 0.02 for adults.

量化捕食行为对幼年和成年腹足类动物的影响对于了解群落的古生态学非常重要。尽管有大量研究检查了成年壳上的捕食行为，但实际上没有报道涉及幼体标本。我们比较了来自墨西哥东部太平洋的上新世组合中的幼年和成年腹足类动物的捕食频率和捕食效果。贝壳中存在钻孔，证实了样品中存在捕食的迹象，这归因于Oichnus simplex Bromley，1981和O. paraboloides Bromley，1981，它们显示了食足类腹足动物的主动捕食。在同一地点钻腹足纲动物的发生揭示了可能的捕食者为杀线虫（Polinices intermeratus）。（Philippi，1853年）和Natica broderipianaRécluz，1844年）和muricids（Eupleura vokesorum Herbert，2005年和Thypina sp。）。在成虫的腹足纲动物之间发现了一些差异，成虫的成虫频率比成虫的成虫频率高，而幼年则相反。猎物有效度（PE）的值是：0.00和0.02。