Dendrorhynchoides curvidentatus (Ji and Ji 1998 - Dendrorhynchus) Tithonian, Late Jurassic or Barremian-age Lower Cretaceous, ~150-130 mya, ~13 cm in length [GMV 2128] was originally considered a rhamphorhynchid due to the long tail, which has since been considered doctored. Interestingly, the doctored tail phylogenetically fit what was known of sister taxa, like MCSNB 8950 until the IVPP embryo became known (which may have reduced its tail independently as it seems to form a clade with Dimorphodon? weintraubi). Dendrorhynchoides was a basal anurognathid derived from a sister to Dimorphodon? weintraubi and phylogenetically preceded the flat-headed anurognathid SMNS 81928. Early workers could not find the sternum, sacrals or manual 4.4, nor could they reconstruct the skull.
Distinct from the IVPP embryo, the skull of Dendrorhynchoides had a shorter and broader premaxilla in which the naris was taller. On the jugal the pre- and postorbital processes were bridged over, creating a shallower orbit. The maxilla was shorter and carried fewer teeth. The lacrimal was S-shaped. The postorbital elements were all shorter and smaller. The teeth were small and uniform. The lateral temporal fenestra was tiny and tucked under the much larger postorbital. The cranium was flatter. The ectopalatines (ectopterygoid fused to palatine) were much larger, the pterygoids much longer and the vomers much shorter as the skull became wider.
The neural spines were all shorter. The dorsal ribs were robust and very broad to articulate with the verky wide sternal complex. This created a voluminous torso. If the caudals are valid, they were longer than in the IVPP embryo, but individually shorter than in MCSNB 8950, so could represent the transitional stage.
The sternal complex was much wider with a convex leading edge. The scapula and coracoid were relatively longer. Distinct from Dimorphodon weintraubi, the humerus was more gracile, with a shape more like that of MCSNB 8950. The metacarpus was very short and manual 4.1 reached the elbow when folded. One gets the impression that anurognathids curled their wings more when folded.
The pelvic elements were all fused and the posterior ilium was truncated. The hind limbs were shorter. Pedal digit II extended further than the others and they all had long unguals. The proximal pedal phalanges were nearly as short as the middle phalanges. Pedal 5.1 extended beyond metatarsal IV.
The specimen GLGMV 0002, was attributed to Dendrorhynchoides (Hone and Lü 2010), but it is not related.
Additional data from the fossil were identified by following the universally criticized methods described here demonstrating the superiority of digital graphic segregaton. |
