A pterosaur bone bed with at least 47 individuals (wing spans: 0.65–2.35 m) of a new species is reported from southern Brazil from an interdunal lake deposit of a Cretaceous desert, shedding new light on several biological aspects of those flying reptiles. The material represents a new pterosaur, Caiuajara dobruskii gen. et sp. nov., that is the southermost occurrence of the edentulous clade Tapejaridae (Tapejarinae, Pterodactyloidea) recovered so far. Caiuajara dobruskii differs from all other members of this clade in several cranial features, including the presence of a ventral sagittal bony expansion projected inside the nasoantorbital fenestra, which is formed by the premaxillae; and features of the lower jaw, like a marked rounded depression in the occlusal concavity of the dentary. Ontogenetic variation of Caiuajara dobruskii is mainly reflected in the size and inclination of the premaxillary crest, changing from small and inclined (∼115°) in juveniles to large and steep (∼90°) in adults. No particular ontogenetic features are observed in postcranial elements. The available information suggests that this species was gregarious, living in colonies, and most likely precocial, being able to fly at a very young age, which might have been a general trend for at least derived pterosaurs.

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Objective: To evaluate the initial forces generated by two types of palatal expansion appliances, through fiber optic sensors, in elastomeric models. Materials and Methods: An elastomeric model simulating the upper dental arch was fabricated. The sensors were placed adjacent to the first premolars and the first molars roots (apical, cervical, vestibular, palatal). Hyrax and Haas palatal expanders were fitted onto the dental arch. Activation of the screw was performed 4 times. The variations in wavelengths of each sensor during the activations were recorded. ANOVA and Games-Howell were used (P <.05). Results: In the first premolars, the force generated by Hyrax was higher than that generated by Haas in the cervical and apical regions of the palatal and vestibular surfaces, respectively; in the first molars, the force was higher in the cervical vestibular region than that in the cervical palatal region for both the appliances; in Hyrax, the force was higher in the apical vestibular than in the apical palatine in tooth 14 (P <.05). There was no difference between the devices for each activation; the total force generated by Hyrax was equal to that of Haas (P <.05). Conclusions: The fiber optic sensors were effective in measuring the initial forces generated by the studied palatal expanders. Hyrax and Haas palatal expanders produced similar forces. Greater force was recorded on the vestibular surfaces.