The definition of a fossil ecological community from fossil associations has always been problematic. Determining coevality of the members of a fossil association has posed one of the most ravelling problems in this matter. However, in case of relicts of fossil reefs, this problem seems, to some extent, solvable due to the frequency of fossil findings in life position. In addition, the interaction between these fossils poses the possibility of performing statistical analyses in order to effectively quantify the relation that existed among the members of a fossil association as well as between fossil associations. In this paper, we present a method to obtain fossil communities by means of a combined algorithm (WPGMA‐Jaccard Index) performed onto 14 fossil associations from the Cipit boulders from the Middle‐to‐Late Triassic St Cassian Formation (Dolomites, Northeastern Italy), which have been previously reported in the literature. Presence/absence data of environmentally diagnostic micro‐encrusters and hexactinellid sponges were input into a matrix, which underwent cluster analysis. This analysis rendered a phenogram, where five different communities (phena) could be recognized. Each community has its particular palaeoenvironmental constraints, defined in turn by the particular array of micro‐encrusters/hexactinellid sponges. The method used in this work could be successfully applied in other Triassic reef deposits, taking into account the extensive amount of reports performed in the last decade.

中文翻译：

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从化石协会到生态群落：以意大利东北部白云岩上拉第尼—下卡尼斯的圣卡西安组的“ Cipit巨石”为例

化石协会对化石生态共同体的定义一直存在问题。确定化石协会成员的便捷性已成为该问题上最棘手的问题之一。但是，在化石礁遗迹的情况下，由于在生活地点发现化石的频率高，这个问题在某种程度上似乎可以解决。另外，这些化石之间的相互作用提供了进行统计分析的可能性，以便有效地量化化石协会成员之间以及化石协会之间存在的关系。在本文中，我们提出了一种通过组合算法（WPGMA-Jaccard指数）获得化石群落的方法，该算法对中晚期三叠纪圣卡西安组（白云岩，意大利东北部）的Cipit巨石的14个化石协会进行了研究，以前在文献中报道过。将环境诊断性微壳和十六进制海绵的存在/不存在数据输入矩阵，然后进行聚类分析。这项分析绘制了一个phenogram，可以识别五个不同的社区（phena）。每个群落都有其特定的古环境约束，依次由微壳/六方海绵的特定阵列来定义。这项工作中使用的方法可以成功地应用于其他三叠纪珊瑚礁矿床，