Rhamphorhynchus is a genus of long-tailed pterosaurs in the Upper Jurassic. It is the best-known of the long-tailed pterosaurs, the sub-order Rhamphorynchoidea.
Rhamphorhynchus had a long tail, stiffened with ligaments, which ended in a small diamond-shaped rudder on the end of its tail which helped keep it stable when it was flying.
The jaws of Rhamphorhynchus housed needle-like teeth, which were angled forward, with a curved, sharp, beak-like tip lacking teeth. Their diet was mainly fish and insects.
Like other pterosaurs, its body was covered with hairs, which suggests it had termperature regulation ('hot-blooded') and a high rate of metabolism. This is also found in birds and bats, and seems necessary for active flight.
The genus was quite successful: it is the most common pterosaur found in the Solnhofen limestone beds in Bavaria, Germany. These are the same strata where Archaeopteryx was found.