A new species of Gobiconodon (Triconodonta, Mammalia) and its implication for the age of Jehol Biota
A new species of Gobiconodon （Triconodonta, Mammalia） and its implication for the age of Jehol Biota

A new species of Gobiconodon is found from the Yixian Formation of western Liaoning, China. The new taxa, G. zofiae sp. nov., has a confluent opening for branches Ⅱ and Ⅲ of the trigeminal nerve on the anterior lamina of the petrosal. G. zofiae sp. nov. is similar to Repenomamus in having an ossified Meckel's cartilage connecting the lower jaws and ear region. The new species, with enlarged I1/I1, posteriorly located infraorbital foramen and four mental foramina, distinctly differs from the other species of Gobiconodon. The new material indicates that Gobiconodon has four, not five, upper molariforms. The presence of Gobiconodon in Jehol Biota makes it possible to correlate Jehol Biota with faunas in eastern Asia and North America, and suggests the age of the Yixian Formation to be Early Cretaceous.