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单词 Euryapsida
释义

Euryapsida

中文百科

调孔亚纲

调孔亚纲的头颅骨
A euryapsid skull.
Zum Vergleich: Der diapside Schädel hat zwei Temporalfenster

调孔亚纲(Euryapsida)又称阔孔亚纲上孔亚纲,是群中生代的海生爬行动物,特征是头骨有大的上颞孔,而缺少下颞孔。牠们与单孔亚纲的差别在于,单孔亚纲的颞颥孔在下方。调孔亚纲是个复系群,这意味者不同演化支彼此并不互相关联,且从不同祖先演化而来。现在普遍认为调孔亚纲其实是多群失去下颞孔的双孔亚纲动物。调孔亚纲现在并不在科学文献中使用,鱼龙超目被分类于双孔亚纲,鳍龙超目则被分类于鳞龙形下纲,包含楯齿龙目、幻龙目、蛇颈龙目。

另一个过去的分类单元「Enaliosauria」,则包含鱼龙目、蛇颈龙目。

英语百科

Euryapsida 调孔亚纲

A euryapsid skull.
调孔亚纲的头颅骨
Zum Vergleich: Der diapside Schädel hat zwei Temporalfenster

Euryapsida is a polyphyletic (unnatural, as the various members are not closely related) group of reptiles that are distinguished by a single temporal fenestra, an opening behind the orbit, under which the post-orbital and squamosal bones articulate. They are different from Synapsida, which also have a single opening behind the orbit, by the placement of the fenestra. In synapsids, this opening is below the articulation of the post-orbital and squamosal bones. It is now commonly believed that euryapsids are in fact diapsids (which have two fenestrae behind the orbit) that lost the lower temporal fenestra. There are no surviving descendants of the euryapsids.

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更新时间:2025/6/20 22:14:38