Abstract Peculiar meniscate burrows with three sediment cords occur in early to middle Miocene tidal-flat deposits of southwestern Japan. Two of the cords are situated at the bottom and the other is at its center. Detailed observations of the burrow structures and comparative neoichnological studies of modern spatangoid burrows in a tidal flat revealed that the former two were true drainage tubes and the latter was fecal in origin. The trace fossil was thus assigned to the ichnogenus Scolicia. Based on these findings, a new ichnospecies Scolicia shirahamensis isp. nov. has been described here. The central sediment cord is seemingly identical to the drainage tube of the ichnogenus Bichordites, another ichnogenus that has been commonly ascribed to a fossil spatangoid burrow, similar to Scolicia. Careless ichnogeneric identification of a spatangoid burrow, based only on the central sediment cord, therefore, may produce an incorrect identification.

中文翻译：

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Scolicia shirahamensis isp。十一月：三线脊柱侧弯及其技术意义

摘要 日本西南部早、中新世潮滩沉积物中发现具有三条沉积索的奇特弯月形洞穴。其中两根绳索位于底部，另一根绳索位于其中心。对潮间带中现代 spatangoid 洞穴的洞穴结构的详细观察和比较新时代研究表明，前两者是真正的引流管，而后者是粪便来源。痕迹化石因此被分配给 ichnogenus Scolicia。基于这些发现，一种新的鱼类物种 Scolicia shirahamensis isp。十一月 已在此处描述。中央沉积带似乎与 ichnogenus Bichordites 的排水管相同，这是另一种 ichnogenus，通常被认为是一个与 Scolicia 相似的化石 spatangoid 洞穴。