Drillholes on shells are one of the few predation marks preserved in fossil molluscs, providing an opportunity to study and quantify predator-prey interactions in the palaeontological record. Among these, reports of drilling predation on scaphopods are rare, and such information from Antarctica is non-existent. We describe the finding of drillholes on scaphopods recovered from Recent mollusc assemblages between depths of 246.5 and 454.0 m in West Antarctica. The predation traces located in the middle sectors of two preyed shells belonging to Siphonodentalium dalli and Dentalium majorinum are identified as Oichnus and are interpreted as produced by naticids, probably Pseudamauropsis aureolutea. These new records constitute the first reports of drilling predation on scaphopods in Antarctica and also for Recent scaphopods of the Southern Hemisphere.

Naticids and muricids are the main drilling gastropod families that leave a characteristic hole in their shelled prey. Drilling predation can be evaluated along spatial scales, and different latitudinal patterns (equatorward, poleward, mid-latitude peaks or no trend at all) have already been described. For Argentine Patagonia, most studies have analysed muricid predation, but scant information is available on naticid predation. This study provides evidence of predation by the moon snail Notocochlis isabelleana on a thin and fragile burrowing bivalve, Darina solenoides, along the intertidal sandflats at Pozo Salado, San Matías Gulf, in northern Patagonia. To estimate the incidence of predation, articulated specimens of Darina solenoides (N = 432) were randomly collected in the intertidal zone. Drill holes (N = 94) were recorded in shell lengths ranging between 10 and 35 mm. Taking into account previous studies in the region, the intensity of mortality by drilling (22%) constitutes a higher value than expected for this latitude. These results may help explain local patterns in a particular site in northern Patagonia which has been previously identified as an outlier, but further studies aimed at evaluating macrogeographic patterns are necessary for a better understanding of the regional factors that might be governing these predator–prey interactions.