Rhamphorhynchus and the True Prow Beaks The last and most

evolved group of long-tailed pterosaurs, the rhamphorhynchids, was not only one of the longest-lived and most diverse clans, but also gave rise to several large species, individuals of which grew to almost 3 meters (about 10 feet) in wingspan. Early in its history, this clan split into two quite different lineages: On the one branch were rhamphorhynchines, distinguished by a formidable-looking array of fang-like teeth that splayed forward and outward from the jaws to form a fish-snagging tooth grab. On the other branch were the scaphognathines. They had fewer, but stronger, well-spaced, upright teeth mounted in a broader, more heavily built jaw that presumably allowed them to go after bigger, heavier prey than their rhamphorhynchine cousins.

Dorygnathus, a medium-size pterosaur from the same Lower Jurassic Posidonia shales of Germany as Campylognathoides, is the earliest known rhamphorhynchine and reached about 1 meter (3 feet) in wingspan. More than 20 skeletons of this pterosaur, some with skulls that positively bristle with fish-grabbing teeth, as Figure 4-9 illustrates, have been recovered, one or two of them with patches of fossilized soft tissues.50 Rhamphorhynchines have also been found in rocks from as far afield as England, Madagascar and China, often as fragmentary isolated remains, although the occasional gem, such as the beautifully preserved uncrushed skull of Cacibupteryx from Cuba, sometimes come to light.

The king of the prow beaks, and beakiest of them all,51 was Rhamphorhyn-chus. At least 200 or 300 examples of this pterosaur (far more than for any other rhamphorhynchoid) have already been recovered from the Solnhofen Limestones, and more are found almost every year.52 One happy consequence of this abundance is that the entire skeletal anatomy, from the point of the beak via every nook and cranny of the braincase to the tip of the toes, has been thoroughly pored over, drawn and described.53 The same goes for the numerous examples of fossilized soft tissues: wing membranes, skin, "hair," claw sheaths, tail flaps and foot webs, which are better known in Rhampho-rhynchus than for almost any other pterosaur.54 Rhamphorhynchus is also one of those rare cases of a pterosaur for which much of the growth series is known, ranging from youngsters less than 30 centimeters (12 inches) from wing tip to wing tip, to big old adults well over a meter (3 feet) in wingspan.

FIGURE 4*9 Rhamphorhynchids, the true prow beaks, represented by the skulls of the rhamphorhynehine Dorygnathus, 5 inches (13 centimeters) long, above; and the scaphognathine Scaphognathus, 4.5 inches (12 centimeters) long, below. (Redrawn from Wellnhofer, 1975.)

Dorygnathus

FIGURE 4*9 Rhamphorhynchids, the true prow beaks, represented by the skulls of the rhamphorhynehine Dorygnathus, 5 inches (13 centimeters) long, above; and the scaphognathine Scaphognathus, 4.5 inches (12 centimeters) long, below. (Redrawn from Wellnhofer, 1975.)

Until recently scaphognathines were far less well-known than rhampho-rhynchines, but a row of new finds in China and the Americas is changing all that. A rich new Middle Jurassic pterosaur site, Cerro Condor in Patagonia, discovered by Ollie Rauhut, a paleontologist now based in Munich, Germany, has just yielded the earliest known scaphognathine,55 while the well-preserved snout of Harpactognathus, found in 1996 in the Upper Jurassic of Wyoming, not only shows that scaphognathines lived in North America, too, but reveals that, like many other pterosaurs, some members of this group also sported large, well-developed crests on the skull.56 This discovery has been dramatically confirmed by Pterorhynchus, a scaphognathine from the Lower Cretaceous of China, wherein the bony part of the cranial crest is continued upward by a large, sail-shaped skin-covered cartilaginous flap.57

Fossil remains of Sordes from Upper Jurassic lake sediments in the Karatau mountains of Kazakhstan, are the best-preserved of any scaphognathine. Nine individuals were collected in the early 1960s and are justly famous for the incredible fidelity and completeness of their fossilized soft tissues, which include rare examples of entire wing membranes and even "hair."58 Last, but not quite least, the clan name bearer, Scaphognathus, illustrated in Figure 4-9, is known from just three skeletons, all from the Solnhofen Limestone?59 The presence of a long tail in the second and third specimens to be found confirmed that Scaphognathus is a rhamphorhynchoid, although because the first example, which was found in the early 1800s, lacked the lower half of the body, it was thought, initially, that this pterosaur was a short-tailed form— a pterodactyloid, the group that we shall consider next.

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