封面介绍

《古脊椎动物学报》2021年第59卷第4期

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  封面说明：4.19亿年前云南曲靖早泥盆世洛赫考夫期西山村组盔甲鱼类生态复原图。最大的真盔甲鱼漫游憨鱼(左前)与硕大云南盔甲鱼(右)和曲靖宽甲鱼(左后)等其他盔甲鱼生活在一起。新的研究进展显示，漫游憨鱼鼻孔两侧和头甲侧缘具有排列整齐的锯齿状小刺，口鳃窗被一个大的外骨骼腹片覆盖，该腹片上装饰着致密细小的瘤点，边缘排列有由腹片和腹环共同支撑形成的6对独立的圆形大鳃孔。盔甲鱼类的鳃孔与现生的鳐类一样，都开口于腹面，指示它们均为底栖鱼类，生活在具泥沙质基底的安静滨海环境中，以滤食海底的有机物碎屑为生。详见本期孟馨媛等人文。(绘图：杨定华)。

  Cover image: Ecological reconstruction of galeaspids from the Xishancun Formation in Qujing, Yunnan Province during the early Lochkovian, Early Devonian (about 419 million year ago), showing the largest eugaleaspiform Nochelaspis maeandrine (left front) together with Yunnanogaleaspis major (right) and Laxaspis qujingensis (left back). The reappraisal indicates that the margins of the median dorsal opening and the headshield of N. maeandrine are aligned with spine-like serrations, and the orobranchial fenestra is covered by a large dermal ventral plate, which is decorated with dense, tiny granular tubercles, and aligned with six pairs of separated, large, and circular branchial openings. The branchial openings of galeaspids are located ventrally as in modern rays, indicating a benthic lifestyle dwelling on sandy or muddy substrates in a quiet marine environment and a filter feeding on organic detritus. See details in the paper of Meng et al. (Illustrated by Yang Dinghua).

发布日期： 2021-11-11  浏览： 1005