A monospecific assemblage of myodocopid ostracods has been found in the Middle Devonian of a unique hydrothermal vent system of Hamar Laghdad (eastern Anti-Atlas, southern Morocco), which developed over a submarine eruption of basaltic rocks. This fauna has been recovered from a neptunian dyke representing the sediment infill of an Eifelian venting fissure discovered in the central part of Hamar Laghdad. The assemblage consists of thousands of relatively large shells forming a coquina layer in which the valves are disarticulated, perfectly washed, well sorted and stacked into each other. Their orientation points to transport due to fluids migrating in the vent system. The ostracod specimens, on the base of the general outline, the presence of rostrum and rostral incisure is assigned to the order Myodocopida. The new genus and species Hamaroconcha kornickeri is proposed, most likely representing a new family. Its carapace morphology gives no clear clue to its mode of life; however, a relatively long rostral incisure may suggest that frontal appendages of this species were sufficient for active swimming. Therefore, a nectobenthic lifestyle is postulated for H. kornickeri nov. gen., nov. sp. Isotope data from the sediment infill provide evidence for the activity of hydrothermal fluids.

中文翻译：

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来自摩洛哥南部艾弗利亚（中泥盆纪）的热液喷口 myodocopid ostracods

在中泥盆世哈马尔拉格达（摩洛哥南部的反阿特拉斯东部）独特的热液喷口系统中发现了一种单种类群介形动物，该喷口系统是在玄武岩海底喷发的基础上发展起来的。这种动物群是从海王星堤坝中发现的，该堤坝代表了在哈马尔拉格达中部发现的埃菲尔喷口裂缝的沉积物填充物。该组合由数千个相对较大的贝壳组成，形成一个 coquina 层，其中阀门被分离、完美清洗、分类良好并相互堆叠。由于流体在通风系统中迁移，它们的方向指向运输。介形虫标本，根据大体轮廓，喙部和喙部切口的存在被归入 Myodocopida 目。提出了新的属和种 Hamaroconcha kornickeri，很可能代表一个新科。它的甲壳形态对其生活方式没有明确的线索。然而，相对较长的喙部切口可能表明该物种的额叶足以进行活跃的游泳。因此，假设 H. kornickeri nov 是一种底栖动物的生活方式。将军，十一月 sp. 来自沉积物填充物的同位素数据为热液流体的活动提供了证据。