封面说明：4.28亿年前志留纪曙鱼(Shuyu)和安吉鱼(Anjiaspis)生态复原图。浙江曙鱼(S. zhejiangensis)和网状安吉鱼(A. reticularis)发现于浙江长兴、安吉等地的志留纪地层，是早期盔甲鱼类的典型代表，标志着无颌类盔甲鱼类的第一次辐射演化。通过同步辐射X射线显微成像对曙鱼侧线系统进行的三维虚拟复原未能发现其感觉管具有任何通向头甲表面的通道，盔甲鱼类的侧线管如何与外界水体沟通仍然是个未解之谜。另外，新的研究表明，安吉鱼所谓的“网状”侧线系统，实系对皮下脉管丛的误判，其真实的侧线系统目前仍不详；盔甲鱼类中原来被认为广泛存在的松果孔，可能只存在于曙鱼等极少数属种中。详见刘玉海等人文。(绘图：杨定华)

Cover image: Ecological reconstruction of Shuyu and Anjiaspis from the Silurian of China (428 million years ago). S. zhejiangensis and A. reticularis, mainly found from the Silurian of Changxing and Anji counties, Zhejiang Province, are typical representatives of early galeaspids, representing the first radiation of galeaspids. Using synchroton radiation X-ray tomography, the 3D virtual reconstruction of Shuyu revealed that no ascending tubes issue from the sensory canals to the surface of the headshield. Therefore, it still remains enigmatic that how the lateral line canals of gleaspids communicate with the current surrounding. In addition, the new observation indicates that the so-called ‘reticulation-like’ lateral line canals of Anjiaspis are actually the subaponeurotic vessels. The real sensory canals in Anjiaspis still remain unknown at present; the so-called pineal opening widely described in galeaspis probably only definitely present in a few forms such as Shuyu.See details in the paper of Liu et al. (Illustrated by Yang Dinghua)