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Many fossil taxa are known only from single specimens, making it difficult to gauge levels of intraspecific, and particularly ontogenetic, variation. Here we report on an aggregation of the Early Cretaceous lizard Dalinghosaurus longidigitus from deposits of the Yixian Formation, China. A single block from the Lujiatun Bed contains parts of at least sixteen three-dimensional skeletons ranging from hatchling to young adult. Taphonomic features suggest the animals were probably part of a natural aggregation caught up and transported by a localised mudslide during a volcanic eruption. The most complete specimens on the block add new information on jaw, palate and braincase morphology for this derived lizard. Dalinghosaurus is now represented by a sample of nearly thirty individuals from hatchling to skeletally mature adult, permitting a discussion of skeletal ontogeny. While the narrow fused frontal, flange-like angular process, strong conical teeth and long feet remain constant features throughout development, there are marked changes in cranial sculpture pattern through ontogeny and more minor changes in skull morphology and limb proportions.