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Tupandactylus
''Tupandactylus'' (meaning "Tupan finger", in reference to the Tupi thunder god) is a genus of tapejarid pterodactyloid pterosaur from the Early Cretaceous Crato Formation of Brazil. It is notable for its large cranial crest, composed partly of bone and partly of soft tissue. The ''Tupandactylus'' genus possibly contains two species, both bearing differently sized/shaped crests that may have been used to signal and display for other ''Tupandactylus'', much as toucans use their bright bills to signal to one another. ''Tupandactylus'' crests consisted of a semicircular crest over the snout, and in the case of the type species ''T. imperator'', a bony prong which extended back behind the head. A second species, ''T. navigans'', lacked this prong, and had a much more vertical crest. Soft tissue impressions also show that the small bony crests were extended by a much larger structure made of a keratinous material. The complete crest of ''T. navigans'' rose in a sharp, sail-like "dome" high above the rest of the skull.
==Description==
''Tupandactylus imperator'' is known from four nearly complete skulls. The holotype specimen is MCT 1622-R, a skull and partial lower jaw, found in the Crato Formation, dating to the boundary of the Aptian-Albian stages of the early Cretaceous period, about 112 Ma ago.〔Martill, D.M., Bechly, G. and Loveridge, R.F. (2007). ''The Crato fossil beds of Brazil: window into an ancient world.'' Cambridge University Press. ISBN 0-521-85867-4, ISBN 978-0-521-85867-0〕 It was initially described as a species of ''Tapejara'', but later research has indicated it warrants its own genus. The skull was toothless and had a prominent sagittal crest, only the base of which was bony: the front of the crest featured a tall bony rod extending up and back, and the rear of the crest had a long prong of bone projecting behind it. The bulk of the crest was made up of soft tissue similar to keratin, supported by the two bony struts. An additional skull described in 2011, specimen CPCA 3590, preserved more of the lower jaw, showing that like ''Tapejara'', ''T. imperator'' had a large, asymmetrical "keel"-like crest on the underside of the lower jaw tip.
Some ''Tupandactylus'' specimens preserve evidence of a keratinous beak at the jaw tips. However, this was restricted to the crested portion of the lower jaw, as one specimen also preserves pycnofibres (simple feather-like filaments) covering the jaws further back.〔
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
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