**披毛殼屬**（學名：，意為「毛茸茸的頭皮」）為雙神經類軟體動物的基幹成員，屬於似楯殼螺目的棱管殼科，生存於奧陶紀早期的特馬豆克階，化石發現於摩洛哥東部。成體可成長至 12 公分左右。

特徵描述
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成體全長最大可達 12 公分，亞成體化石全長小於 2 公分。外型大致呈長橢圓狀，約在頭部的位置上方有一個明顯的大型殼板（anterior shell plate），但大部分表面都被外套膜和骨片（英语：）覆蓋。背部生有細小而密集的體刺。具有齒舌構造，分為鉤狀（uncinal teeth）及外側的齒舌（lateral teeth）。

命名與詞源
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披毛殼的屬名由兩個字結合衍化而來，分別是指頭皮的「*calva*」，以及「*pilosus*」（意為「多毛的」），兩個字都是來自拉丁文，形容這種身上密布細針狀物的原始軟體動物。種名則是為了感謝在美國耶魯大學的館藏標本中「發現」了這種奇特生物化石的古生物學家 Björn Kröger，故取其姓氏命名。

發現歷史
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目前已知的披毛殼屬化石共有七具，它們都是由化石收藏家穆罕默德·班莫拉（Mohamed 'Ou Said' Ben Moula）在2000年代後期於摩洛哥東部的札戈拉（英语：）一帶，一個被稱為費札瓦塔組（英语：）（Fezouata Formation）的地層中發現的，該地層是典型的伯吉斯頁岩型頁岩層（Burgess shale-type deposits），在奧陶紀時期曾擁有生物相豐富的費札瓦塔生物群（Fezouata Biota），也因此班莫拉在這裡發現了數百件，甚至數千件已化石化的軟組織標本。而班莫拉和美國耶魯大學的古生物學家有工作上的關係，因此這些科學家有幸得以將這些化石標本運回耶魯大學進行進一步的研究。

班莫拉提供的化石中，共有七具披毛殼化石，但當時它們並沒有立即被注意到，而是如上所述，是後來才在耶魯大學眾多的館藏標本中被發現的。在這七具披毛殼化石中，有兩具分別為成體和亞成體的標本被完整的保存下來，足以讓科學家仔細研究其生理上的構造和細部特徵。從化石中明顯能看見披毛殼的頭部具有類似頭盔的殼，顯示早期的軟體動物可能就已經具有殼的構造。

另一個引起不少科學家關注的特徵是，部分披毛殼標本的齒舌構造被完整保存下來，這向來是軟體動物特有且普遍的器官，上面有超過125排的「小牙齒」，對於披毛殼而言，這些所謂的「小牙齒」能用來翻找食物，像是附著在岩石上的海藻。佩瑞表示，披毛殼的齒舌原本是位在其頭部的殼下面的，但殼已在化石形成的過程中消失，可以看見這些「小牙齒」被印壓在殼上。

演化關係
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|   | 無殼綱 Aplacophora （包含絕大多數現存的深海軟體動物） |
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|   | 多殼綱 Polyplacophora （包含現存的石鱉） |
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|   | *Protobalanus* |
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|   | *Polysacos* |
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|   | *Echinochiton* |
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|   | 哈氏蟲屬 *Halkieria* |
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|   | 黎鐮蟲屬 *Orthrozanclus* |
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|   | 棱管殼屬 *Siphogonuchites* |
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|   | **披毛殼屬 *Calvapilosa*** |
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|   | 有殼亞門 Conchifera （包含絕大多數現存的有殼軟體動物，如蝸牛、蛞蝓、蛤蜊、烏賊等） |
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參考文獻
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1. 1 2 3 4  Vinther, J.; Parry, L.; Briggs, D. E. G.; Van Roy, P.. Nature. 2017, **542** (7642): 471–474  [2021-04-07]. ISSN 0028-0836. doi:10.1038/nature21055. （原始内容存档于2021-09-30）.
2. ↑  Van Roy, P.; Orr, P. J.; Botting, J. P.; Muir, L. A.; Vinther, J.; Lefebvre, B.; El Hariri, K.; Briggs, D. E. G.. Nature. 2010, **465**: 215–218  [2017-02-13]. ISSN 0028-0836. doi:10.1038/nature09038. （原始内容存档于2017-02-14）.
3. 1 2 3  Nicola Davis.. The Guardian. February 6, 2017  [2017-02-13]. （原始内容存档于2020-11-12）.
4. 1 2 3  Laura Geggel.. Live Science. February 6, 2017  [2017-02-13]. （原始内容存档于2020-12-25）.

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| 分類單元識別碼 | 
* 维基数据: Q28845503
* Fossilworks: 350430
* GBIF: 9522631

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