ABSTRACT Species of the genus Lithophyllum are important carbonate producers and bioconstructors. In recent years, molecular studies focusing on this genus have unravelled several striking cases of cryptic and pseudocryptic diversity. Lithophyllum racemus is a common non-geniculate coralline alga-forming rhodoliths in the northeastern Atlantic Ocean and the Mediterranean Sea. Molecular phylogenies (psbA and coxI) reconstructed for some Mediterranean specimens morpho-anatomically assigned to L. racemus revealed two well-supported sister clades. Based on pairwise sequence divergences, we recognised these two clades as separate species, L. racemus and L. pseudoracemus sp. nov. The low number of specimens has not permitted any useful morpho-anatomical comparison between the species, and for now, only DNA sequencing permits separation. The discovery of L. pseudoracemus unravelled a new case of cryptic diversity in Mediterranean coralline algae, highlighting the substantially underestimated diversity of these seaweeds.

中文翻译：

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来自地中海西部的总状石叶藻（Corallinales，Rhodophyta）的边界揭示了石叶藻属的物种。十一月

摘要 Lithophyllum 属的物种是重要的碳酸盐生产者和生物构造者。近年来，专注于该属的分子研究揭示了几个引人注目的隐性和假隐性多样性案例。Lithophyllum racemus 是大西洋东北部和地中海常见的非膝状珊瑚藻形成的红石藻。为一些地中海标本重建的分子系统发育（psbA 和 coxI）在形态解剖学上分配给 L. racemus 揭示了两个得到充分支持的姐妹进化枝。基于成对序列差异，我们将这两个进化枝识别为单独的物种，L.racemus 和 L.pseudoracemus sp。十一月 样本数量少，无法在物种之间进行任何有用的形态解剖比较，目前，只有 DNA 测序允许分离。