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Destiny of the New Papers

I haven't clapped eyes on any of these papers yet...

Schwarz, D., Ikejiri, T., Breithaupt, B.H., Sander, P.M., and Klein, N. (2007). A nearly complete skeleton of an early juvenile diplodocid (Dinosauria: Sauropoda) from the Lower Morrison Formation (Late Jurassic) of north central Wyoming and its implications for early ontogeny and pneumaticity in sauropods. Historical Biology 19: 225-253.

Abstract: "A nearly complete skeleton of a juvenile sauropod from the Lower Morrison Formation (Late Jurassic, Kimmeridgian) of the Howe Ranch in Bighorn County, Wyoming is described. The specimen consists of articulated mid-cervical to mid-caudal vertebrae and most appendicular bones, but cranial and mandibular elements are missing. The shoulder height is approximately 67 cm, and the total body length is estimated to be less than 200 cm. Besides the body size, the following morphological features indicate that this specimen is an early juvenile; (1) unfused centra and neural arches in presacral, sacral and first to ninth caudal vertebrae, (2) unfused coracoid and scapula, (3) open coracoid foramen, and (4) relatively smooth articular surfaces on the limb, wrist, and ankle bones. A large scapula, short neck and tail and elongate forelimb bones relative to overall body size demonstrate relative growth. A thin-section of the mid-shaft of a femur shows a lack of annual growth lines, indicating an early juvenile individual possibly younger than a few years old. Pneumatic structures in the vertebral column of the specimen SMA 0009 show that pneumatisation of the postcranial skeleton had already started in this individual, giving new insights in the early ontogenetic development of vertebral pneumaticity in sauropods.

"The specimen exhibits a number of diplodocid features (e.g., very elongate slender scapular blade with a gradually dorsoventrally expanded distal end, a total of nine dorsal vertebrae, presence of the posterior centroparapophyseal lamina in the posterior dorsal vertebrae). Although a few diplodocid taxa, _Diplodocus_, cf. _Apatosaurus_, and cf. _Barosaurus_, are known from several fossil sites near the Howe Ranch, identification of this specimen, even at a generic level, is difficult due to a large degree of ontogenetic variation."

And for the choristodere fans...

Ke-Qin Gao, Ksepka, D., Hou Lianhai, Duan Ye, and Hu Dongyu (2007). Cranial morphology of an Early Cretaceous monjurosuchid (Reptilia: Diapsida) from Liaoning Province of China and evolution of the choristoderan palate. Historical Biology 19: 215-224.

Abstract: "A new specimen of _Philydrosaurus proseilus_ from the Early Cretaceous Chiufotang (Jiufotang) Formation preserves the first complete palate of a monjurosuchid choristodere. As in other choristoderes, the palate of _Philydrosaurus_ is akinetic, extended by a broad contact between the vomer and maxilla, and equipped with multiple batteries of palatal teeth. This specimen provides phylogenetically significant information and clarifies the distribution of many apomorphies within Choristodera. _Philydrosaurus_ is primitive relative to the Neochoristodera in that it exhibits only a moderate degree of posterior displacement of the choanae and retains a relatively large interpterygoid vacuity. However, _Philydrosaurus_ also exhibits several derived features previously considered diagnostic of the Neochoristodera, including establishment of a long midline contact of the pterygoids and development of a distinct nasopalatal trough extending from the choana. The choristodere palate exhibits significant modification of the primitive diapsid condition, including elongation of the vomers, establishment of a vomer-maxilla contact, posterior displacement of the choanae, development of the nasopalatal trough, and reduction of the interpterygoid vacuity."

Katsura, Y. (2007). Fusion of sacrals and anatomy in _Champsosaurus_ (Diapsida, Choristodera). Historical Biology 19: 263-271.

Abstract: "Sacral centra are occasionally fused with or without severe deformation in _Champsosaurus_ (Diapsida, Choristodera). The sympatrical occurrence of fusion and non-fusion of sacra in adults through their evolution questions that sacral fusion represents the final form of a simple ontogenetic change or specific variation. Females are proposed to possess more robust limb bones than males because they are considered to have been more terrestrial due to the nesting behaviour on land. The coincidental occurrence of fusion of sacral centra without severe deformation and more robust limb bones in same individuals suggests that sacral fusion is a phenomenon occurring in females as a result of terrestrial adaptation for reproductive activities. Sacral fusion associated with severe deformation is considered a pathological condition although its etiology and factors remain undefined."

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