Conspicuous morphological differentiation without speciation in <i>Anemonia viridis</i> (Cnidaria, Actiniaria)

<i>Anemonia viridis</i> is a model species for studies of physiological and transcriptomic response to symbiosis and environmental stress (temperature, light, symbiosis breakdown). Five morphs are described in this species, based on morphology, pigment protein content, and major mode of reproduction. Up to now, the taxonomic status of these morphs remains unclear, without clear knowledge of whether the morphological variation amongst the morphs is due to phenotypic plasticity or adaptation. In the present study, we assess the species status of the three most commonly found morphs by coalescent analyses. For this purpose, five markers were designed for genes whose expression is modified under stress (<i>ca2m</i>, <i>duf140</i>, <i>RNAbinding5</i>, <i>tyrK</i>, <i>sym32</i>) and analysed in 34 individuals representing the morphs <i>A. viridis</i> var <i>rufescens</i>, <i>rustica</i> and <i>smaragdina</i> from eight geographic sites (two in the English Channel and six in the Mediterranean Sea). Phylogenetic analyses of individual gene trees showed no clear separation of the morphs. Furthermore, multilocus coalescent analyses using SpedeSTEM and BPP regrouped all the morphs into one species, showing very few genetic differences amongst them. In a further analysis, we checked for clonality amongst 80 individuals of <i>A. viridis</i> var. <i>smaragdina</i> from one geographic site using three microsatellite loci. This morph proved to be as clonal as var. <i>rustica</i>, indicating a similar potential for asexual reproduction.绿海葵（<i>Anemonia viridis</i>）是研究共生与环境胁迫（温度、光照、共生体解体）下生理与转录组响应的模式物种。该物种目前已依据形态学特征、色素蛋白含量以及主要繁殖方式划分出5个形态型。截至目前，这些形态型的分类地位仍不明确，学界尚未明确其形态差异究竟源于表型可塑性还是适应性演化。本研究通过溯祖分析，对该物种最常见的3个形态型的物种分类地位进行了评估。为此，我们针对胁迫下表达量发生改变的基因（<i>ca2m</i>、<i>duf140</i>、<i>RNAbinding5</i>、<i>tyrK</i>、<i>sym32</i>）设计了5个分子标记，并对采自8个地理种群（英吉利海峡2个、地中海6个）的34个个体进行了分析，这些个体分别代表绿海葵红肤变种（<i>A. viridis</i> var <i>rufescens</i>）、<i>rustica</i>形态型以及<i>smaragdina</i>形态型。单基因树的系统发育分析结果显示，各形态型之间并无明显的遗传分化。此外，利用SpedeSTEM和BPP进行的多位点溯祖分析将所有形态型归为同一物种，表明它们之间的遗传差异极小。在后续分析中，我们利用3个微卫星位点，对采自单个地理种群的80个<i>A. viridis</i> var. <i>smaragdina</i>个体进行了克隆性检测。结果显示，该形态型与<i>rustica</i>变种具有同等的克隆繁殖能力，表明二者具备相似的无性繁殖潜力。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于海葵物种Anemonia viridis，旨在探究其显著形态分化是否伴随物种形成。研究通过遗传分析（包括五个标记基因和微卫星位点）发现，尽管存在多个形态，但所有形态被归为同一物种，遗传差异极小，表明分化主要由表型可塑性或适应驱动，而非物种形成。数据集还评估了无性繁殖潜力，并提供了相关实验数据和资助信息。