Sexually Dimorphic Hamipterus tianshanensis and Their Tridimensionally Preserved Eggs
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Fig.1 Photo (A) and Line Drawing (B) of Hamipterus tianshanensis (IVPP V18931) in a Large Block of the Early Cretaceous deposit of the Turpan-Hami Basin, south of the Tian Shan Mountains in Xinjiang, northwestern China. This block preserves three skulls, including a complete female skull (holotype, IVPP V18931.1), an incomplete female skull (IVPP V18931.2), and an incomplete male skull (IVPP V18931.3), Scale bar, 10 cm. (Image by WANG Xiaolin)
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Fig.2 Hamipterus tianshanensis with abundant bones and tridimensional eggs. (A), a block (IVPP V18932) with an incomplete skull (IVPP V18932.1) closely associated with an egg (IVPP V18932.2) and a right humerus. The skull is interpreted as belonging to a male due to the large and robust cranial crest, starting above the fifth tooth position. The crest shows developed anteriorly curved ridges and sulci and an arc-shaped anterior margin. Scale bar, 10 cm. (B) Close-up of the deformed egg. Scale bar, 1 cm. (Image by WANG Xiaolin)
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Fig.3 Male and Female Skulls of Hamipterus tianshanensis (A) and (E) are females; (B), (D), and (F) are males; (C) Outline of holotype showing female crest, gray part with white lines shows male crest. Male skulls have larger and thicker crests than female skulls; male crests also have more strongly curved anterior margins than female crests and are positioned more anteriorly. (Image by WANG Xiaolin)
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Fig.4 Comparison of Eggs of Hamipterus tianshanensis (Left) and the Colubrid Snake Elaphe (Right). (Image by WANG Xiaolin)
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Fig.5 Life reconstruction of Hamipterus tianshanensis (Image by ZHAO Chuan)