Featherstars, comatulid crinoids that shed their stalk during their ontogeny, are the most species‐rich lineage of modern crinoids and the only ones present in shallow water today. Although they are of considerable palaeontological interest as a ‘success story’ of the Mesozoic Marine Revolution, their fossil record is relatively species‐poor and fragmentary. New Spanish fossils of the Cretaceous featherstar Decameros ricordeanus preserve the shape and configuration of nervous and circulatory anatomy in the form of infilled cavities, which we reconstruct from CT scans. The circulatory system of D. ricordeanus was relatively extensive and complex, implying a pattern of coelomic fluid flow that is unique among crinoids, and the peripheral parts of the nervous system include linkages both to the circulatory system and to the surface of the body. A phylogenetic analysis (the first to include both living and fossil featherstars and which includes characters from internal anatomy) recovers D. ricordeanus among the lineage of featherstars that includes Himerometroidea, Tropiometra and ‘Antedonoidea’, among others. D. ricordeanus is larger than almost any modern featherstar, and its elaborate coelomic morphology appears to be a consequence of positive allometry. All featherstars with coelomic diverticula are shown to belong to a single comatulid subclade, and this feature may constitute a synapomorphy of that group. Some preservation of cavities corresponding to soft tissue is probably not exceptional in fossil crinoids, providing an opportunity to study the diversity and evolution of extinct anatomical systems typically only preserved in Lagerstätten.

中文翻译：

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白垩纪海百合的神经和循环系统：保存，古生物学和进化意义

Featherstars是在个体发育过程中脱落的茎状杂化海藻类，是现代海藻类中物种最多的谱系，也是当今浅水区中仅有的种。尽管作为中生代海洋革命的“成功故事”，它们在古生物学上具有相当大的兴趣，但它们的化石记录相对而言物种贫乏且支离破碎。西班牙白垩纪羽毛之星Decameros ricordeanus的新化石以填充空腔的形式保存了神经和循环解剖结构的形状和构造，我们从CT扫描中重建了这些形状和构造。循环系统D. ricordeanus它是相对广泛而复杂的，这意味着在促流素中独特的腔速流体流动模式，而神经系统的外围部分包括与循环系统和身体表面的连接。系统发育分析（第一个同时包括活体和化石羽毛星，并且包括内部解剖学特征的人）在羽毛星系中检索了D. ricordeanus，其中包括喜马拉雅线虫，Tropiometra和“ Antedonoidea”等。D.ricordeanus它比几乎任何现代羽状羽毛星都大，并且其精细的腔隙形态似乎是正异形的结果。所有带有羽状憩室的羽状星都显示为属于一个单一的小分支，并且此特征可能构成该组的突触。在化石类海百合中，一些与软组织相对应的空腔的保存可能并非例外，这为研究通常仅保存在Lagerstätten中的绝种解剖系统的多样性和进化提供了机会。