Brasileodactylus araripensis was first named by Alexander Kellner in 1984 and was based on a portion of the lower jaw of a new kind of pterosaur. Over the years, several new specimens have been discovered including a complete skull and parts of the rest of the skeleton. It is known from the Lower Cretaceous Santana Formation of Ceará, Brazil, deposited about 115 million year ago.
The skull is almost completely known, only missing the very tips of both jaws. It has a very long and narrow snout, with many cone-shaped teeth. The teeth are quite long at the ends of the jaws and become much smaller as they approach the jaw joint. The jaw tips widen slightly, but they show no signs of any crests on the snout or chin. The complete skull is 43 cm (17 inches) long, and the other skull fragments are from similarly sized individuals.
The remainder of the skeleton is represented by several specimens which include vertebrae from the neck and back, as well as portions of the shoulder and wing. Comparison to other pterosaurs suggests a wingspan of about 2.5 meters (8 feet).
Brasileodactylus is an ornithocheirid, from a large family of short-tailed pterosaurs characterized by long toothy snouts, relatively short necks, and long narrow wings perfect for soaring over the water. Several ornithocheirids have semi-circular crests at or near the tips of their jaws, but Brasileodactylus falls outside of that lineage. Ornithocheirids are closely related to the toothless pteranodontids and nyctosaurids, both families that were also primarily marine fishers.
Brasileodactylus has only been found in near-shore marine sediments of the Santana Formation, formed under the waves of the incipient Atlantic Ocean. Brasileodactylus preyed on fish, squid, and ammonites, plucking them from near the surface. The longer teeth at the tips of the jaws helped snatch prey items, and the shorter teeth farther back allowed food to be held onto as it moved into the throat. It shared its environment with several other medium- to large-sized pterosaurs including close relatives Anhanguera, Barbosania, Cearadactylus, and Maaradactylus, as well as several crested toothless azhdarchoids including Banguela, Tapejara, Thalassodromeus, and Tupuxuara.