Sexually Dimorphic Hamipterus tianshanensis and Their Tridimensionally Preserved Eggs
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)
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)
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)
Fig.4 Comparison of Eggs of Hamipterus tianshanensis (Left) and the Colubrid Snake Elaphe (Right). (Image by WANG Xiaolin)
Fig.5 Life reconstruction of Hamipterus tianshanensis (Image by ZHAO Chuan)