Evidence for tactile foraging in pterosaurs: a sensitive tip to the beak of Lonchodraco giganteus (Pterosauria, Lonchodectidae) from the Upper Cretaceous of southern England

The sense of touch is important for hunting and feeding in vertebrates, especially when visual cues are unreliable. Foramina in the jaws and face, associated with nerves and sensory organs, may provide information about feeding. Pterosaurs, many of which had large, well-developed eyes, are often assumed to have been visual feeders. Here, we show that the lonchodectid pterosaur Lonchodraco giganteus (Bowerbank, 1846) has clusters of circular foramina at the anterior mandibular symphysis (the odontoid) and on the lateral margins of the rostrum that indicate enhanced sensitivity of the rostrum tip. This pattern implies tactile foraging. The foramina were likely occupied by Herbst corpuscles or similar integumentary sensory micro-organs (ISO). They presumably served a sensory function at the jaw tip to enhance food gathering. A similar morphology occurs in some avians that feed using tactile cues, including probe feeders such as kiwis, sandpipers, and ibises, tactile hunters such as spoonbills, and filter feeders such as ducks and flamingos. The beak morphology of L. giganteus does not closely resemble that of these birds, and thus its modus operandi for feeding remains speculative, however tactile foraging for fish or invertebrates in shallow water seems likely. Like birds, pterosaurs evolved a diverse range of feeding strategies.