干旱区生态环境知识资源中心

The echinoid genus Amblypygus Agassiz is reported for the first time from the middle Miocene and is represented by a new species, A. matruhensis sp. nov., from the area west of Mersa Matruh, Western Desert, Egypt. This extends the range of Amblypygus from the lower Eocene to the middle Miocene. A morphological comparison between the two genera Amblypygus and Echinoneus shows that they differ in that Amblypygus has a semi-ethmolytic apical disc and crenulate, perforate tubercles whereas Echinoneus has an ethmophract apical disc and non-crenulate, non-perforate tubercles. The paleoecology and the paleogeography of the genus Amblypygus are discussed.