中国辽西早白垩世义县组始无齿翼龙新材料

摘要

The diagnostic features of Eopteranodon are amended on the basis of new material. The amended features are as follows: the neural spines in the mid cervical vertebrae are absent; the ratio of the length of the deltopectoral crest to the humerus length is approximately 0.25; and the length of the metacarpal Ⅳ is almost equal to the length of the second wing phalange; the ratio of the length of wing phalange 2 to wing phalange 1 is approximately 0.76. The new specimen of Eopteranodon is slightly different from its holotype, probably due to ontogenetic development.%根据新材料,对始无齿翼龙的特征进行了修订:中部颈椎体没有神经棘;肱骨三角嵴的长度与肱骨长度之比率约为0.25;翼掌骨的长度与第二翼指骨的长度几乎相等;第二翼指骨与第一翼指骨的长度之比率约为0.76.始无齿翼龙的新标本与正型稍微不同,可能由个体发育所引起.