封面说明：叶氏南雄脊齿兽(Nanxiongilambda yei)头部复原图。依据下颌及牙齿特征，产于广东南雄盆地中古新统浓山组的南雄脊齿兽，被归入已经绝灭的“古老有蹄类”全齿目全棱兽科。此前全棱兽科化石仅发现于北美早-中古新世地层，南雄脊齿兽的发现扩展了全棱兽类的分布范围，而且它还是亚洲首次发现晚古新世之前与北美类群具有明确亲缘关系的新生代哺乳动物，表明全棱兽类很可能在早古新世晚期-中古新世早期经历了一次从北美到东亚的迁徙。详见本期权硕硕和王元青文。(绘图：陈瑜)
Cover image: Head reconstruction of Nanxiongilambda yei gen. et sp. nov. Nanxiongilambda from the Middle Paleocene Nongshan Formation of the Nanxiong Basin, Guangdong Province, China is a pantolambdid, belonging to the order Pantodonta, an extinct group of “archaic ungulates”. Members of Pantolambdidae were previously only known from the lower–middle Paleocene in North America. This finding extends the geographical distribution of Pantolambdidae. Nanxiongilambda yei represents the first known Asian Cenozoic mammal with reliable North American affinity prior to the Late Paleocene, which indicates a particular wave of migration from North America to Asia during the late Early-early Middle Paleocene. See details in the paper of Quan and Wang. (Illustrated by Chen Yu).
