Paleoecology of naticid-molluscan prey interaction during the Late Jurassic (Oxfordian) in Kutch, India: Evolutionary implications

We document and quantify one of the oldest predator-prey interactions between naticid gastropods and molluscan prey, based on drill holes in shells, from the Late Jurassic (Oxfordian) beds of Kutch, western India. Previously, many workers recorded naticid-like drill holes on prey taxa from the Triassic and the Jurassic, but in the absence of associated naticid body fossils, they remained equivocal. The present gastropod community is dominated by turritellines (98% of the sample) which form the TDA (turritelline-dominated assemblage) and the naticid drilling predation is almost entirely restricted to turritellines among gastropods. Confamilial naticid predation takes place occasionally. Within the bivalve community, corbulids and nuculids are most abundant and are drilled more often than other taxa. These observations indicate that prey selection was opportunistic and solely based on availability. Drilling intensities at both assemblage and lower taxon levels are low. Behavioural ster...本研究基于印度西部卡奇（Kutch）盆地晚侏罗世（牛津阶）地层中的壳体生物钻孔，记录并量化了玉螺类腹足动物（naticid gastropods）与软体动物猎物（molluscan prey）之间已知最古老的捕食关系之一。此前，诸多学者曾在三叠纪（Triassic）与侏罗纪（Jurassic）的猎物类群中记录到类似玉螺类的生物钻孔，但由于缺乏伴随产出的玉螺类实体化石（body fossils），相关结论始终存疑。 本次研究涉及的腹足类群落以锥螺类腹足动物（turritellines）为主，其占样品总量的98%，构成锥螺主导组合（TDA, turritelline-dominated assemblage）；玉螺类的钻孔捕食行为几乎仅针对该群落中的锥螺类，仅偶尔发生同科玉螺类捕食（confamilial naticid predation）。双壳类群落中，篮蛤科（corbulids）与胡桃蛤科（nuculids）最为丰富，且相较于其他类群更易被钻孔。上述观测结果表明，捕食选择具有机会主义特征，仅取决于猎物的可获得性。无论是在群落水平还是低级分类单元（lower taxon）水平，钻孔强度均较低。捕食行为的……