Fig. 3 in First record of a Late Jurassic rhamphorhynchine pterosaur from Gondwana

Fig. 3. Rhamphorhynchinae gen. et sp. indet. (MUHNCAL.20165) from Cerritos Bayos, west Calama, Chile; Cerro Campamento Formation, middle Oxfordian. Left humerus in dorsal (A1, A5), posterodorsal (A2, A6), posterior (A3, A7), and ventral (A4, A8) views, photographs (A1–A4) and explanatory drawings (A5–A8). Zone of Subvinialesphinctes prophetae and Euaspidoceras centrum. However, we cannot assure that this ratio is natusp., middle Oxfordian. ral since the vertebral centrum is not complete. Only one in- Descriptions.—Vertebra: Among the remains there is a sin- complete transverse process is preserved (preserved length gle incomplete vertebra (Fig. 2). This is visible in articular of ~4.5 mm). This arises from the top of the neural arch and view and it is very eroded; it is difficult to stablish whether has a dorsolateral orientation. Proximally, the height of the it is exposed in anterior, posterior, or in an approximately transverse process represents almost half of the centrum oblique view. The neural spine is tall (preserved height is height, narrowing distally. Due to its incompleteness, its 6.3 mm), as described for Rhamphorhynchinae (Witton extension cannot be established. The neural canal is broad, 2013: 129) especially in the cervical vertebrae, although rel- being wider than high and representing ca. three fifths of atively tall and rectancular neural spines are also seen in the the preserved centrum width. The poor preservation of the anterior dorsal vertebrae of Rhamphorhynchus (see Bonde material makes it difficult to assess the exact shape and and Christiansen 2003: fig. 5). The neural spine is laterally proportions of the neural canal, although it appears to have compressed and slightly higher than the preserved vertebral a dorsoventrally compressed oval shape. The centrum is图3 产自智利卡拉马西部塞里托斯巴约斯、坎帕门托山组（Cerro Campamento Formation）牛津阶中期的喙嘴龙亚科（Rhamphorhynchinae）未定属种（gen. et sp. indet.）标本（MUHNCAL.20165）。其左肱骨（left humerus）分别以背视（dorsal view）（A1、A5）、后背视（posterodorsal view）（A2、A6）、后视（posterior view）（A3、A7）及腹视（ventral view）（A4、A8）呈现，其中A1–A4为实物照片（photographs），A5–A8为解说线图（explanatory drawings）。该标本产自Subvinialesphinctes prophetae与真盾菊石（Euaspidoceras）centrum生物带。不过由于椎体（vertebral centrum）不完整，我们无法确定该比值是否合理。 描述——脊椎：本次出土遗存中仅包含一枚不完整的脊椎（vertebra）（图2）。该脊椎呈关节面视角且已严重侵蚀，难以判断其暴露面为前视、后视还是近似斜向视角。神经棘（neural spine）保留高度约6.3 mm，相对高耸，符合喙嘴龙亚科的特征（Witton, 2013: 129），该特征在颈椎（cervical vertebrae）中尤为显著；不过喙嘴龙（Rhamphorhynchus）的前背椎（anterior dorsal vertebrae）也可见相对高而呈矩形的神经棘（参见Bonde与Christiansen 2003：图5）。该神经棘侧向压缩，高度略高于所保留的椎体。仅存一枚不完整的横突（transverse process），保留长度约4.5 mm，其起自神经弓（neural arch）顶部，朝向背外侧。近端（proximally）横突的高度几乎达到椎体高度的一半，并向远端（distally）逐渐变细。由于该横突不完整，无法确定其延伸范围。神经管（neural canal）较宽，宽大于高，约占保留椎体宽度的五分之三。因标本保存状况不佳，难以确定神经管的确切形态与比例，不过其整体似乎呈背腹向压缩的卵圆形。椎体