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Whatcheeria
''Whatcheeria'' is an extinct genus of early tetrapod from the Early Carboniferous of Iowa. Fossils have been found in 340 million year old fissure fill deposits in the town of Delta. The type species ''W. deltae'' was named in 1995. It is classified within the family Whatcheeriidae along with the closely related ''Pederpes''.
== Description ==
''Whatcheeria'' possesses a mixture of both primitive and derived traits. It shares with earlier stem tetrapods a series of lateral lines across the skull, rows of teeth on the palate, and small Meckelian foramina across the surface of the lower jaw. It has a cleithrum, a bone in the pectoral girdle that extends from the scapula. The cleithrum once attached to the skull in lobe-finned fish, the ancestors of tetrapods, but detached to allow the neck to move freely.
''Whatcheeria'' grew to about long. The skull is deep and the snout is pointed. A hole on the top of the skull behind the eyes called the parietal foramen is relatively large in ''Whatcheeria''. The bones on the skull surface are unusually smooth, unlike the pitted skulls of many other early tetrapods. In front of the eye socket, the prefrontal bone forms a prominent ridge. The prefrontal also projects downward to cover a possible sinus.〔
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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